1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * https://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.text;
18
19 import java.io.IOException;
20 import java.io.Reader;
21 import java.io.Serializable;
22 import java.io.Writer;
23 import java.nio.CharBuffer;
24 import java.util.Arrays;
25 import java.util.Iterator;
26 import java.util.List;
27 import java.util.Objects;
28
29 import org.apache.commons.lang3.ArrayUtils;
30 import org.apache.commons.lang3.StringUtils;
31 import org.apache.commons.text.matcher.StringMatcher;
32
33 /**
34 * Builds a string from constituent parts providing a more flexible and powerful API than {@link StringBuffer} and
35 * {@link StringBuilder}.
36 * <p>
37 * The main differences from StringBuffer/StringBuilder are:
38 * </p>
39 * <ul>
40 * <li>Not synchronized</li>
41 * <li>Not final</li>
42 * <li>Subclasses have direct access to character array</li>
43 * <li>Additional methods
44 * <ul>
45 * <li>appendWithSeparators - adds an array of values, with a separator</li>
46 * <li>appendPadding - adds a length padding characters</li>
47 * <li>appendFixedLength - adds a fixed width field to the builder</li>
48 * <li>toCharArray/getChars - simpler ways to get a range of the character array</li>
49 * <li>delete - delete char or string</li>
50 * <li>replace - search and replace for a char or string</li>
51 * <li>leftString/rightString/midString - substring without exceptions</li>
52 * <li>contains - whether the builder contains a char or string</li>
53 * <li>size/clear/isEmpty - collections style API methods</li>
54 * </ul>
55 * </li>
56 * <li>Views
57 * <ul>
58 * <li>asTokenizer - uses the internal buffer as the source of a StrTokenizer</li>
59 * <li>asReader - uses the internal buffer as the source of a Reader</li>
60 * <li>asWriter - allows a Writer to write directly to the internal buffer</li>
61 * </ul>
62 * </li>
63 * </ul>
64 * <p>
65 * The aim has been to provide an API that mimics very closely what StringBuffer provides, but with additional methods.
66 * It should be noted that some edge cases, with invalid indices or null input, have been altered - see individual
67 * methods. The biggest of these changes is that by default, null will not output the text 'null'. This can be
68 * controlled by a property, {@link #setNullText(String)}.
69 * </p>
70 * <p>
71 * This class is called {@code TextStringBuilder} instead of {@code StringBuilder} to avoid clashing with
72 * {@link StringBuilder}.
73 * </p>
74 *
75 * @since 1.3
76 */
77 public class TextStringBuilder implements CharSequence, Appendable, Serializable, Builder<String> {
78
79 /**
80 * Inner class to allow StrBuilder to operate as a reader.
81 */
82 final class TextStringBuilderReader extends Reader {
83
84 /** The last mark position. */
85 private int mark;
86
87 /** The current stream position. */
88 private int pos;
89
90 /**
91 * Default constructor.
92 */
93 TextStringBuilderReader() {
94 }
95
96 /** {@inheritDoc} */
97 @Override
98 public void close() {
99 // do nothing
100 }
101
102 /** {@inheritDoc} */
103 @Override
104 public void mark(final int readAheadLimit) {
105 mark = pos;
106 }
107
108 /** {@inheritDoc} */
109 @Override
110 public boolean markSupported() {
111 return true;
112 }
113
114 /** {@inheritDoc} */
115 @Override
116 public int read() {
117 if (!ready()) {
118 return -1;
119 }
120 return charAt(pos++);
121 }
122
123 /** {@inheritDoc} */
124 @Override
125 public int read(final char[] b, final int off, int len) {
126 if (off < 0 || len < 0 || off > b.length || off + len > b.length || off + len < 0) {
127 throw new IndexOutOfBoundsException();
128 }
129 if (len == 0) {
130 return 0;
131 }
132 if (pos >= size()) {
133 return -1;
134 }
135 if (pos + len > size()) {
136 len = size() - pos;
137 }
138 TextStringBuilder.this.getChars(pos, pos + len, b, off);
139 pos += len;
140 return len;
141 }
142
143 /** {@inheritDoc} */
144 @Override
145 public boolean ready() {
146 return pos < size();
147 }
148
149 /** {@inheritDoc} */
150 @Override
151 public void reset() {
152 pos = mark;
153 }
154
155 /** {@inheritDoc} */
156 @Override
157 public long skip(long n) {
158 if (pos + n > size()) {
159 n = size() - pos;
160 }
161 if (n < 0) {
162 return 0;
163 }
164 pos = Math.addExact(pos, Math.toIntExact(n));
165 return n;
166 }
167 }
168
169 /**
170 * Inner class to allow StrBuilder to operate as a tokenizer.
171 */
172 final class TextStringBuilderTokenizer extends StringTokenizer {
173
174 /**
175 * Default constructor.
176 */
177 TextStringBuilderTokenizer() {
178 }
179
180 /** {@inheritDoc} */
181 @Override
182 public String getContent() {
183 final String str = super.getContent();
184 if (str == null) {
185 return TextStringBuilder.this.toString();
186 }
187 return str;
188 }
189
190 /** {@inheritDoc} */
191 @Override
192 protected List<String> tokenize(final char[] chars, final int offset, final int count) {
193 if (chars == null) {
194 return super.tokenize(getBuffer(), 0, TextStringBuilder.this.size());
195 }
196 return super.tokenize(chars, offset, count);
197 }
198 }
199
200 /**
201 * Inner class to allow StrBuilder to operate as a writer.
202 */
203 final class TextStringBuilderWriter extends Writer {
204
205 /**
206 * Default constructor.
207 */
208 TextStringBuilderWriter() {
209 }
210
211 /** {@inheritDoc} */
212 @Override
213 public void close() {
214 // do nothing
215 }
216
217 /** {@inheritDoc} */
218 @Override
219 public void flush() {
220 // do nothing
221 }
222
223 /** {@inheritDoc} */
224 @Override
225 public void write(final char[] cbuf) {
226 TextStringBuilder.this.append(cbuf);
227 }
228
229 /** {@inheritDoc} */
230 @Override
231 public void write(final char[] cbuf, final int off, final int len) {
232 TextStringBuilder.this.append(cbuf, off, len);
233 }
234
235 /** {@inheritDoc} */
236 @Override
237 public void write(final int c) {
238 TextStringBuilder.this.append((char) c);
239 }
240
241 /** {@inheritDoc} */
242 @Override
243 public void write(final String str) {
244 TextStringBuilder.this.append(str);
245 }
246
247 /** {@inheritDoc} */
248 @Override
249 public void write(final String str, final int off, final int len) {
250 TextStringBuilder.this.append(str, off, len);
251 }
252 }
253
254 /** The space character. */
255 private static final char SPACE = ' ';
256
257 /**
258 * The extra capacity for new builders.
259 */
260 static final int CAPACITY = 32;
261
262 /**
263 * End-Of-Stream.
264 */
265 private static final int EOS = -1;
266
267 /**
268 * The size of the string {@code "false"}.
269 */
270 private static final int FALSE_STRING_SIZE = Boolean.FALSE.toString().length();
271
272 /**
273 * Required for serialization support.
274 *
275 * @see java.io.Serializable
276 */
277 private static final long serialVersionUID = 1L;
278
279 /**
280 * The size of the string {@code "true"}.
281 */
282 private static final int TRUE_STRING_SIZE = Boolean.TRUE.toString().length();
283
284 /**
285 * The maximum size buffer to allocate.
286 *
287 * <p>This is set to the same size used in the JDK {@link java.util.ArrayList}:</p>
288 * <blockquote>
289 * Some VMs reserve some header words in an array.
290 * Attempts to allocate larger arrays may result in
291 * OutOfMemoryError: Requested array size exceeds VM limit.
292 * </blockquote>
293 */
294 private static final int MAX_BUFFER_SIZE = Integer.MAX_VALUE - 8;
295
296 /**
297 * Creates a positive capacity at least as large the minimum required capacity.
298 * If the minimum capacity is negative then this throws an OutOfMemoryError as no array
299 * can be allocated.
300 *
301 * @param minCapacity the minimum capacity
302 * @return the capacity
303 * @throws OutOfMemoryError if the {@code minCapacity} is negative
304 */
305 private static int createPositiveCapacity(final int minCapacity) {
306 if (minCapacity < 0) {
307 // overflow
308 throw new OutOfMemoryError("Unable to allocate array size: " + Integer.toUnsignedString(minCapacity));
309 }
310 // This is called when we require buffer expansion to a very big array.
311 // Use the conservative maximum buffer size if possible, otherwise the biggest required.
312 //
313 // Note: In this situation JDK 1.8 java.util.ArrayList returns Integer.MAX_VALUE.
314 // This excludes some VMs that can exceed MAX_BUFFER_SIZE but not allocate a full
315 // Integer.MAX_VALUE length array.
316 // The result is that we may have to allocate an array of this size more than once if
317 // the capacity must be expanded again.
318 return Math.max(minCapacity, MAX_BUFFER_SIZE);
319 }
320
321 /**
322 * Constructs an instance from a reference to a character array. Changes to the input chars are reflected in this
323 * instance until the internal buffer needs to be reallocated. Using a reference to an array allows the instance to
324 * be initialized without copying the input array.
325 *
326 * @param initialBuffer The initial array that will back the new builder.
327 * @return A new instance.
328 * @since 1.9
329 */
330 public static TextStringBuilder wrap(final char[] initialBuffer) {
331 Objects.requireNonNull(initialBuffer, "initialBuffer");
332 return new TextStringBuilder(initialBuffer, initialBuffer.length);
333 }
334
335 /**
336 * Constructs an instance from a reference to a character array. Changes to the input chars are reflected in this
337 * instance until the internal buffer needs to be reallocated. Using a reference to an array allows the instance to
338 * be initialized without copying the input array.
339 *
340 * @param initialBuffer The initial array that will back the new builder.
341 * @param length The length of the subarray to be used; must be non-negative and no larger than
342 * {@code initialBuffer.length}. The new builder's size will be set to {@code length}.
343 * @return A new instance.
344 * @since 1.9
345 */
346 public static TextStringBuilder wrap(final char[] initialBuffer, final int length) {
347 return new TextStringBuilder(initialBuffer, length);
348 }
349
350 /** Internal data storage. */
351 private char[] buffer;
352
353 /**
354 * The new line, {@code null} means use the system default from {@link System#lineSeparator()}.
355 */
356 private String newLine;
357
358 /** The null text. */
359 private String nullText;
360
361 /** Incremented when the buffer is reallocated. */
362 private int reallocations;
363
364 /** Current size of the buffer. */
365 private int size;
366
367 /**
368 * Constructs an empty builder with an initial capacity of 32 characters.
369 */
370 public TextStringBuilder() {
371 this(CAPACITY);
372 }
373
374 /**
375 * Constructs an instance from a reference to a character array.
376 *
377 * @param initialBuffer a reference to a character array, must not be null.
378 * @param length The length of the subarray to be used; must be non-negative and no larger than
379 * {@code initialBuffer.length}. The new builder's size will be set to {@code length}.
380 * @throws NullPointerException If {@code initialBuffer} is null.
381 * @throws IllegalArgumentException if {@code length} is bad.
382 */
383 private TextStringBuilder(final char[] initialBuffer, final int length) {
384 this.buffer = Objects.requireNonNull(initialBuffer, "initialBuffer");
385 if (length < 0 || length > initialBuffer.length) {
386 throw new IllegalArgumentException("initialBuffer.length=" + initialBuffer.length + ", length=" + length);
387 }
388 this.size = length;
389 }
390
391 /**
392 * Constructs an instance from a character sequence, allocating 32 extra characters for growth.
393 *
394 * @param seq the string to copy, null treated as blank string
395 * @since 1.9
396 */
397 public TextStringBuilder(final CharSequence seq) {
398 this(StringUtils.length(seq) + CAPACITY);
399 if (seq != null) {
400 append(seq);
401 }
402 }
403
404 /**
405 * Constructs an instance with the specified initial capacity.
406 *
407 * @param initialCapacity the initial capacity, zero or less will be converted to 32
408 */
409 public TextStringBuilder(final int initialCapacity) {
410 buffer = new char[initialCapacity <= 0 ? CAPACITY : initialCapacity];
411 }
412
413 /**
414 * Constructs an instance from a string, allocating 32 extra characters for growth.
415 *
416 * @param str the string to copy, null treated as blank string
417 */
418 public TextStringBuilder(final String str) {
419 this(StringUtils.length(str) + CAPACITY);
420 if (str != null) {
421 append(str);
422 }
423 }
424
425 /**
426 * Appends a boolean value to the string builder.
427 *
428 * @param value the value to append
429 * @return this, to enable chaining
430 */
431 public TextStringBuilder append(final boolean value) {
432 if (value) {
433 ensureCapacityInternal(size + TRUE_STRING_SIZE);
434 appendTrue(size);
435 } else {
436 ensureCapacityInternal(size + FALSE_STRING_SIZE);
437 appendFalse(size);
438 }
439 return this;
440 }
441
442 /**
443 * Appends a char value to the string builder.
444 *
445 * @param ch the value to append
446 * @return this, to enable chaining
447 */
448 @Override
449 public TextStringBuilder append(final char ch) {
450 final int len = length();
451 ensureCapacityInternal(len + 1);
452 buffer[size++] = ch;
453 return this;
454 }
455
456 /**
457 * Appends a char array to the string builder. Appending null will call {@link #appendNull()}.
458 *
459 * @param chars the char array to append
460 * @return this, to enable chaining
461 */
462 public TextStringBuilder append(final char[] chars) {
463 if (chars == null) {
464 return appendNull();
465 }
466 final int strLen = chars.length;
467 if (strLen > 0) {
468 final int len = length();
469 ensureCapacityInternal(len + strLen);
470 System.arraycopy(chars, 0, buffer, len, strLen);
471 size += strLen;
472 }
473 return this;
474 }
475
476 /**
477 * Appends a char array to the string builder. Appending null will call {@link #appendNull()}.
478 *
479 * @param chars the char array to append
480 * @param startIndex the start index, inclusive, must be valid
481 * @param length the length to append, must be valid
482 * @return this, to enable chaining
483 * @throws StringIndexOutOfBoundsException if {@code startIndex} is not in the
484 * range {@code 0 <= startIndex <= chars.length}
485 * @throws StringIndexOutOfBoundsException if {@code length < 0}
486 * @throws StringIndexOutOfBoundsException if {@code startIndex + length > chars.length}
487 */
488 public TextStringBuilder append(final char[] chars, final int startIndex, final int length) {
489 if (chars == null) {
490 return appendNull();
491 }
492 if (startIndex < 0 || startIndex > chars.length) {
493 throw new StringIndexOutOfBoundsException("Invalid startIndex: " + length);
494 }
495 if (length < 0 || startIndex + length > chars.length) {
496 throw new StringIndexOutOfBoundsException("Invalid length: " + length);
497 }
498 if (length > 0) {
499 final int len = length();
500 ensureCapacityInternal(len + length);
501 System.arraycopy(chars, startIndex, buffer, len, length);
502 size += length;
503 }
504 return this;
505 }
506
507 /**
508 * Appends the contents of a char buffer to this string builder. Appending null will call {@link #appendNull()}.
509 *
510 * @param str the char buffer to append
511 * @return this, to enable chaining
512 */
513 public TextStringBuilder append(final CharBuffer str) {
514 return append(str, 0, StringUtils.length(str));
515 }
516
517 /**
518 * Appends the contents of a char buffer to this string builder. Appending null will call {@link #appendNull()}.
519 *
520 * @param buf the char buffer to append
521 * @param startIndex the start index, inclusive, must be valid
522 * @param length the length to append, must be valid
523 * @return this, to enable chaining
524 */
525 public TextStringBuilder append(final CharBuffer buf, final int startIndex, final int length) {
526 if (buf == null) {
527 return appendNull();
528 }
529 if (buf.hasArray()) {
530 final int totalLength = buf.remaining();
531 if (startIndex < 0 || startIndex > totalLength) {
532 throw new StringIndexOutOfBoundsException("startIndex must be valid");
533 }
534 if (length < 0 || startIndex + length > totalLength) {
535 throw new StringIndexOutOfBoundsException("length must be valid");
536 }
537 final int len = length();
538 ensureCapacityInternal(len + length);
539 System.arraycopy(buf.array(), buf.arrayOffset() + buf.position() + startIndex, buffer, len, length);
540 size += length;
541 } else {
542 append(buf.toString(), startIndex, length);
543 }
544 return this;
545 }
546
547 /**
548 * Appends a CharSequence to this string builder. Appending null will call {@link #appendNull()}.
549 *
550 * @param seq the CharSequence to append
551 * @return this, to enable chaining
552 */
553 @Override
554 public TextStringBuilder append(final CharSequence seq) {
555 if (seq == null) {
556 return appendNull();
557 }
558 if (seq instanceof TextStringBuilder) {
559 return append((TextStringBuilder) seq);
560 }
561 if (seq instanceof StringBuilder) {
562 return append((StringBuilder) seq);
563 }
564 if (seq instanceof StringBuffer) {
565 return append((StringBuffer) seq);
566 }
567 if (seq instanceof CharBuffer) {
568 return append((CharBuffer) seq);
569 }
570 return append(seq.toString());
571 }
572
573 /**
574 * Appends part of a CharSequence to this string builder. Appending null will call {@link #appendNull()}.
575 *
576 * @param seq the CharSequence to append
577 * @param startIndex the start index, inclusive, must be valid
578 * @param endIndex the end index, exclusive, must be valid
579 * @return this, to enable chaining
580 */
581 @Override
582 public TextStringBuilder append(final CharSequence seq, final int startIndex, final int endIndex) {
583 if (seq == null) {
584 return appendNull();
585 }
586 if (endIndex <= 0) {
587 throw new StringIndexOutOfBoundsException("endIndex must be valid");
588 }
589 if (startIndex >= endIndex) {
590 throw new StringIndexOutOfBoundsException("endIndex must be greater than startIndex");
591 }
592 return append(seq.toString(), startIndex, endIndex - startIndex);
593 }
594
595 /**
596 * Appends a double value to the string builder using {@code String.valueOf}.
597 *
598 * @param value the value to append
599 * @return this, to enable chaining
600 */
601 public TextStringBuilder append(final double value) {
602 return append(String.valueOf(value));
603 }
604
605 /**
606 * Appends a float value to the string builder using {@code String.valueOf}.
607 *
608 * @param value the value to append
609 * @return this, to enable chaining
610 */
611 public TextStringBuilder append(final float value) {
612 return append(String.valueOf(value));
613 }
614
615 /**
616 * Appends an int value to the string builder using {@code String.valueOf}.
617 *
618 * @param value the value to append
619 * @return this, to enable chaining
620 */
621 public TextStringBuilder append(final int value) {
622 return append(String.valueOf(value));
623 }
624
625 /**
626 * Appends a long value to the string builder using {@code String.valueOf}.
627 *
628 * @param value the value to append
629 * @return this, to enable chaining
630 */
631 public TextStringBuilder append(final long value) {
632 return append(String.valueOf(value));
633 }
634
635 /**
636 * Appends an object to this string builder. Appending null will call {@link #appendNull()}.
637 *
638 * @param obj the object to append.
639 * @return this, to enable chaining.
640 */
641 public TextStringBuilder append(final Object obj) {
642 if (obj == null) {
643 return appendNull();
644 }
645 if (obj instanceof CharSequence) {
646 return append((CharSequence) obj);
647 }
648 return append(obj.toString());
649 }
650
651 /**
652 * Appends a string to this string builder. Appending null will call {@link #appendNull()}.
653 *
654 * @param str the string to append
655 * @return this, to enable chaining
656 */
657 public TextStringBuilder append(final String str) {
658 return append(str, 0, StringUtils.length(str));
659 }
660
661 /**
662 * Appends part of a string to this string builder. Appending null will call {@link #appendNull()}.
663 *
664 * @param str the string to append
665 * @param startIndex the start index, inclusive, must be valid
666 * @param length the length to append, must be valid
667 * @return this, to enable chaining
668 * @throws StringIndexOutOfBoundsException if {@code startIndex} is not in the
669 * range {@code 0 <= startIndex <= str.length()}
670 * @throws StringIndexOutOfBoundsException if {@code length < 0}
671 * @throws StringIndexOutOfBoundsException if {@code startIndex + length > str.length()}
672 */
673 public TextStringBuilder append(final String str, final int startIndex, final int length) {
674 if (str == null) {
675 return appendNull();
676 }
677 if (startIndex < 0 || startIndex > str.length()) {
678 throw new StringIndexOutOfBoundsException("startIndex must be valid");
679 }
680 if (length < 0 || startIndex + length > str.length()) {
681 throw new StringIndexOutOfBoundsException("length must be valid");
682 }
683 if (length > 0) {
684 final int len = length();
685 ensureCapacityInternal(len + length);
686 str.getChars(startIndex, startIndex + length, buffer, len);
687 size += length;
688 }
689 return this;
690 }
691
692 /**
693 * Calls {@link String#format(String, Object...)} and appends the result.
694 *
695 * @param format the format string
696 * @param objs the objects to use in the format string
697 * @return {@code this} to enable chaining
698 * @see String#format(String, Object...)
699 */
700 public TextStringBuilder append(final String format, final Object... objs) {
701 return append(String.format(format, objs));
702 }
703
704 /**
705 * Appends a string buffer to this string builder. Appending null will call {@link #appendNull()}.
706 *
707 * @param str the string buffer to append
708 * @return this, to enable chaining
709 */
710 public TextStringBuilder append(final StringBuffer str) {
711 return append(str, 0, StringUtils.length(str));
712 }
713
714 /**
715 * Appends part of a string buffer to this string builder. Appending null will call {@link #appendNull()}.
716 *
717 * @param str the string to append
718 * @param startIndex the start index, inclusive, must be valid
719 * @param length the length to append, must be valid
720 * @return this, to enable chaining
721 */
722 public TextStringBuilder append(final StringBuffer str, final int startIndex, final int length) {
723 if (str == null) {
724 return appendNull();
725 }
726 if (startIndex < 0 || startIndex > str.length()) {
727 throw new StringIndexOutOfBoundsException("startIndex must be valid");
728 }
729 if (length < 0 || startIndex + length > str.length()) {
730 throw new StringIndexOutOfBoundsException("length must be valid");
731 }
732 if (length > 0) {
733 final int len = length();
734 ensureCapacityInternal(len + length);
735 str.getChars(startIndex, startIndex + length, buffer, len);
736 size += length;
737 }
738 return this;
739 }
740
741 /**
742 * Appends a StringBuilder to this string builder. Appending null will call {@link #appendNull()}.
743 *
744 * @param str the StringBuilder to append
745 * @return this, to enable chaining
746 */
747 public TextStringBuilder append(final StringBuilder str) {
748 return append(str, 0, StringUtils.length(str));
749 }
750
751 /**
752 * Appends part of a StringBuilder to this string builder. Appending null will call {@link #appendNull()}.
753 *
754 * @param str the StringBuilder to append
755 * @param startIndex the start index, inclusive, must be valid
756 * @param length the length to append, must be valid
757 * @return this, to enable chaining
758 */
759 public TextStringBuilder append(final StringBuilder str, final int startIndex, final int length) {
760 if (str == null) {
761 return appendNull();
762 }
763 if (startIndex < 0 || startIndex > str.length()) {
764 throw new StringIndexOutOfBoundsException("startIndex must be valid");
765 }
766 if (length < 0 || startIndex + length > str.length()) {
767 throw new StringIndexOutOfBoundsException("length must be valid");
768 }
769 if (length > 0) {
770 final int len = length();
771 ensureCapacityInternal(len + length);
772 str.getChars(startIndex, startIndex + length, buffer, len);
773 size += length;
774 }
775 return this;
776 }
777
778 /**
779 * Appends another string builder to this string builder. Appending null will call {@link #appendNull()}.
780 *
781 * @param str the string builder to append
782 * @return this, to enable chaining
783 */
784 public TextStringBuilder append(final TextStringBuilder str) {
785 return append(str, 0, StringUtils.length(str));
786 }
787
788 /**
789 * Appends part of a string builder to this string builder. Appending null will call {@link #appendNull()}.
790 *
791 * @param str the string to append
792 * @param startIndex the start index, inclusive, must be valid
793 * @param length the length to append, must be valid
794 * @return this, to enable chaining
795 */
796 public TextStringBuilder append(final TextStringBuilder str, final int startIndex, final int length) {
797 if (str == null) {
798 return appendNull();
799 }
800 if (startIndex < 0 || startIndex > str.length()) {
801 throw new StringIndexOutOfBoundsException("startIndex must be valid");
802 }
803 if (length < 0 || startIndex + length > str.length()) {
804 throw new StringIndexOutOfBoundsException("length must be valid");
805 }
806 if (length > 0) {
807 final int len = length();
808 ensureCapacityInternal(len + length);
809 str.getChars(startIndex, startIndex + length, buffer, len);
810 size += length;
811 }
812 return this;
813 }
814
815 /**
816 * Appends each item in an iterable to the builder without any separators. Appending a null iterable will have no
817 * effect. Each object is appended using {@link #append(Object)}.
818 *
819 * @param iterable the iterable to append
820 * @return this, to enable chaining
821 */
822 public TextStringBuilder appendAll(final Iterable<?> iterable) {
823 if (iterable != null) {
824 iterable.forEach(this::append);
825 }
826 return this;
827 }
828
829 /**
830 * Appends each item in an iterator to the builder without any separators. Appending a null iterator will have no
831 * effect. Each object is appended using {@link #append(Object)}.
832 *
833 * @param it the iterator to append
834 * @return this, to enable chaining
835 */
836 public TextStringBuilder appendAll(final Iterator<?> it) {
837 if (it != null) {
838 it.forEachRemaining(this::append);
839 }
840 return this;
841 }
842
843 /**
844 * Appends each item in an array to the builder without any separators. Appending a null array will have no effect.
845 * Each object is appended using {@link #append(Object)}.
846 *
847 * @param <T> the element type
848 * @param array the array to append
849 * @return this, to enable chaining
850 */
851 public <T> TextStringBuilder appendAll(@SuppressWarnings("unchecked") final T... array) {
852 /*
853 * @SuppressWarnings used to hide warning about vararg usage. We cannot use @SafeVarargs, since this method is
854 * not final. Using @SuppressWarnings is fine, because it isn't inherited by subclasses, so each subclass must
855 * vouch for itself whether its use of 'array' is safe.
856 */
857 if (array != null && array.length > 0) {
858 for (final Object element : array) {
859 append(element);
860 }
861 }
862 return this;
863 }
864
865 /** Appends {@code "false"}. */
866 private void appendFalse(int index) {
867 buffer[index++] = 'f';
868 buffer[index++] = 'a';
869 buffer[index++] = 'l';
870 buffer[index++] = 's';
871 buffer[index] = 'e';
872 size += FALSE_STRING_SIZE;
873 }
874
875 /**
876 * Appends an object to the builder padding on the left to a fixed width. The {@code String.valueOf} of the
877 * {@code int} value is used. If the formatted value is larger than the length, the left hand side is lost.
878 *
879 * @param value the value to append
880 * @param width the fixed field width, zero or negative has no effect
881 * @param padChar the pad character to use
882 * @return this, to enable chaining
883 */
884 public TextStringBuilder appendFixedWidthPadLeft(final int value, final int width, final char padChar) {
885 return appendFixedWidthPadLeft(String.valueOf(value), width, padChar);
886 }
887
888 /**
889 * Appends an object to the builder padding on the left to a fixed width. The {@code toString} of the object is
890 * used. If the object is larger than the length, the left hand side is lost. If the object is null, the null text
891 * value is used.
892 *
893 * @param obj the object to append, null uses null text
894 * @param width the fixed field width, zero or negative has no effect
895 * @param padChar the pad character to use
896 * @return this, to enable chaining
897 */
898 public TextStringBuilder appendFixedWidthPadLeft(final Object obj, final int width, final char padChar) {
899 if (width > 0) {
900 ensureCapacityInternal(size + width);
901 String str = Objects.toString(obj, getNullText());
902 if (str == null) {
903 str = StringUtils.EMPTY;
904 }
905 final int strLen = str.length();
906 if (strLen >= width) {
907 str.getChars(strLen - width, strLen, buffer, size);
908 } else {
909 final int padLen = width - strLen;
910 final int toIndex = size + padLen;
911 Arrays.fill(buffer, size, toIndex, padChar);
912 str.getChars(0, strLen, buffer, toIndex);
913 }
914 size += width;
915 }
916 return this;
917 }
918
919 /**
920 * Appends an object to the builder padding on the right to a fixed length. The {@code String.valueOf} of the
921 * {@code int} value is used. If the object is larger than the length, the right hand side is lost.
922 *
923 * @param value the value to append
924 * @param width the fixed field width, zero or negative has no effect
925 * @param padChar the pad character to use
926 * @return this, to enable chaining
927 */
928 public TextStringBuilder appendFixedWidthPadRight(final int value, final int width, final char padChar) {
929 return appendFixedWidthPadRight(String.valueOf(value), width, padChar);
930 }
931
932 /**
933 * Appends an object to the builder padding on the right to a fixed length. The {@code toString} of the object is
934 * used. If the object is larger than the length, the right hand side is lost. If the object is null, null text
935 * value is used.
936 *
937 * @param obj the object to append, null uses null text
938 * @param width the fixed field width, zero or negative has no effect
939 * @param padChar the pad character to use
940 * @return this, to enable chaining
941 */
942 public TextStringBuilder appendFixedWidthPadRight(final Object obj, final int width, final char padChar) {
943 if (width > 0) {
944 ensureCapacityInternal(size + width);
945 String str = Objects.toString(obj, getNullText());
946 if (str == null) {
947 str = StringUtils.EMPTY;
948 }
949 final int strLen = str.length();
950 if (strLen >= width) {
951 str.getChars(0, width, buffer, size);
952 } else {
953 str.getChars(0, strLen, buffer, size);
954 final int fromIndex = size + strLen;
955 Arrays.fill(buffer, fromIndex, fromIndex + width - strLen, padChar);
956 }
957 size += width;
958 }
959 return this;
960 }
961
962 /**
963 * Appends a boolean value followed by a new line to the string builder.
964 *
965 * @param value the value to append
966 * @return this, to enable chaining
967 */
968 public TextStringBuilder appendln(final boolean value) {
969 return append(value).appendNewLine();
970 }
971
972 /**
973 * Appends a char value followed by a new line to the string builder.
974 *
975 * @param ch the value to append
976 * @return this, to enable chaining
977 */
978 public TextStringBuilder appendln(final char ch) {
979 return append(ch).appendNewLine();
980 }
981
982 /**
983 * Appends a char array followed by a new line to the string builder. Appending null will call
984 * {@link #appendNull()}.
985 *
986 * @param chars the char array to append
987 * @return this, to enable chaining
988 */
989 public TextStringBuilder appendln(final char[] chars) {
990 return append(chars).appendNewLine();
991 }
992
993 /**
994 * Appends a char array followed by a new line to the string builder. Appending null will call
995 * {@link #appendNull()}.
996 *
997 * @param chars the char array to append
998 * @param startIndex the start index, inclusive, must be valid
999 * @param length the length to append, must be valid
1000 * @return this, to enable chaining
1001 */
1002 public TextStringBuilder appendln(final char[] chars, final int startIndex, final int length) {
1003 return append(chars, startIndex, length).appendNewLine();
1004 }
1005
1006 /**
1007 * Appends a double value followed by a new line to the string builder using {@code String.valueOf}.
1008 *
1009 * @param value the value to append
1010 * @return this, to enable chaining
1011 */
1012 public TextStringBuilder appendln(final double value) {
1013 return append(value).appendNewLine();
1014 }
1015
1016 /**
1017 * Appends a float value followed by a new line to the string builder using {@code String.valueOf}.
1018 *
1019 * @param value the value to append
1020 * @return this, to enable chaining
1021 */
1022 public TextStringBuilder appendln(final float value) {
1023 return append(value).appendNewLine();
1024 }
1025
1026 /**
1027 * Appends an int value followed by a new line to the string builder using {@code String.valueOf}.
1028 *
1029 * @param value the value to append
1030 * @return this, to enable chaining
1031 */
1032 public TextStringBuilder appendln(final int value) {
1033 return append(value).appendNewLine();
1034 }
1035
1036 /**
1037 * Appends a long value followed by a new line to the string builder using {@code String.valueOf}.
1038 *
1039 * @param value the value to append
1040 * @return this, to enable chaining
1041 */
1042 public TextStringBuilder appendln(final long value) {
1043 return append(value).appendNewLine();
1044 }
1045
1046 /**
1047 * Appends an object followed by a new line to this string builder. Appending null will call {@link #appendNull()}.
1048 *
1049 * @param obj the object to append
1050 * @return this, to enable chaining
1051 */
1052 public TextStringBuilder appendln(final Object obj) {
1053 return append(obj).appendNewLine();
1054 }
1055
1056 /**
1057 * Appends a string followed by a new line to this string builder. Appending null will call {@link #appendNull()}.
1058 *
1059 * @param str the string to append
1060 * @return this, to enable chaining
1061 */
1062 public TextStringBuilder appendln(final String str) {
1063 return append(str).appendNewLine();
1064 }
1065
1066 /**
1067 * Appends part of a string followed by a new line to this string builder. Appending null will call
1068 * {@link #appendNull()}.
1069 *
1070 * @param str the string to append
1071 * @param startIndex the start index, inclusive, must be valid
1072 * @param length the length to append, must be valid
1073 * @return this, to enable chaining
1074 */
1075 public TextStringBuilder appendln(final String str, final int startIndex, final int length) {
1076 return append(str, startIndex, length).appendNewLine();
1077 }
1078
1079 /**
1080 * Calls {@link String#format(String, Object...)} and appends the result.
1081 *
1082 * @param format the format string
1083 * @param objs the objects to use in the format string
1084 * @return {@code this} to enable chaining
1085 * @see String#format(String, Object...)
1086 */
1087 public TextStringBuilder appendln(final String format, final Object... objs) {
1088 return append(format, objs).appendNewLine();
1089 }
1090
1091 /**
1092 * Appends a string buffer followed by a new line to this string builder. Appending null will call
1093 * {@link #appendNull()}.
1094 *
1095 * @param str the string buffer to append
1096 * @return this, to enable chaining
1097 */
1098 public TextStringBuilder appendln(final StringBuffer str) {
1099 return append(str).appendNewLine();
1100 }
1101
1102 /**
1103 * Appends part of a string buffer followed by a new line to this string builder. Appending null will call
1104 * {@link #appendNull()}.
1105 *
1106 * @param str the string to append
1107 * @param startIndex the start index, inclusive, must be valid
1108 * @param length the length to append, must be valid
1109 * @return this, to enable chaining
1110 */
1111 public TextStringBuilder appendln(final StringBuffer str, final int startIndex, final int length) {
1112 return append(str, startIndex, length).appendNewLine();
1113 }
1114
1115 /**
1116 * Appends a string builder followed by a new line to this string builder. Appending null will call
1117 * {@link #appendNull()}.
1118 *
1119 * @param str the string builder to append
1120 * @return this, to enable chaining
1121 */
1122 public TextStringBuilder appendln(final StringBuilder str) {
1123 return append(str).appendNewLine();
1124 }
1125
1126 /**
1127 * Appends part of a string builder followed by a new line to this string builder. Appending null will call
1128 * {@link #appendNull()}.
1129 *
1130 * @param str the string builder to append
1131 * @param startIndex the start index, inclusive, must be valid
1132 * @param length the length to append, must be valid
1133 * @return this, to enable chaining
1134 */
1135 public TextStringBuilder appendln(final StringBuilder str, final int startIndex, final int length) {
1136 return append(str, startIndex, length).appendNewLine();
1137 }
1138
1139 /**
1140 * Appends another string builder followed by a new line to this string builder. Appending null will call
1141 * {@link #appendNull()}.
1142 *
1143 * @param str the string builder to append
1144 * @return this, to enable chaining
1145 */
1146 public TextStringBuilder appendln(final TextStringBuilder str) {
1147 return append(str).appendNewLine();
1148 }
1149
1150 /**
1151 * Appends part of a string builder followed by a new line to this string builder. Appending null will call
1152 * {@link #appendNull()}.
1153 *
1154 * @param str the string to append
1155 * @param startIndex the start index, inclusive, must be valid
1156 * @param length the length to append, must be valid
1157 * @return this, to enable chaining
1158 */
1159 public TextStringBuilder appendln(final TextStringBuilder str, final int startIndex, final int length) {
1160 return append(str, startIndex, length).appendNewLine();
1161 }
1162
1163 /**
1164 * Appends this builder's new line string to this builder.
1165 * <p>
1166 * By default, the new line is the system default from {@link System#lineSeparator()}.
1167 * </p>
1168 * <p>
1169 * The new line string can be changed using {@link #setNewLineText(String)}. For example, you can use this to force the output to always use Unix line
1170 * endings even when on Windows.
1171 * </p>
1172 *
1173 * @return this
1174 * @see #getNewLineText()
1175 * @see #setNewLineText(String)
1176 */
1177 public TextStringBuilder appendNewLine() {
1178 if (newLine == null) {
1179 append(System.lineSeparator());
1180 return this;
1181 }
1182 return append(newLine);
1183 }
1184
1185 /**
1186 * Appends the text representing {@code null} to this string builder.
1187 *
1188 * @return this, to enable chaining
1189 */
1190 public TextStringBuilder appendNull() {
1191 if (nullText == null) {
1192 return this;
1193 }
1194 return append(nullText);
1195 }
1196
1197 /**
1198 * Appends the pad character to the builder the specified number of times.
1199 *
1200 * @param length the length to append, negative means no append
1201 * @param padChar the character to append
1202 * @return this, to enable chaining
1203 */
1204 public TextStringBuilder appendPadding(final int length, final char padChar) {
1205 if (length >= 0) {
1206 ensureCapacityInternal(size + length);
1207 for (int i = 0; i < length; i++) {
1208 buffer[size++] = padChar;
1209 }
1210 }
1211 return this;
1212 }
1213
1214 /**
1215 * Appends a separator if the builder is currently non-empty. The separator is appended using {@link #append(char)}.
1216 * <p>
1217 * This method is useful for adding a separator each time around the loop except the first.
1218 * </p>
1219 *
1220 * <pre>
1221 * for (Iterator it = list.iterator(); it.hasNext();) {
1222 * appendSeparator(',');
1223 * append(it.next());
1224 * }
1225 * </pre>
1226 *
1227 * <p>
1228 * Note that for this simple example, you should use {@link #appendWithSeparators(Iterable, String)}.
1229 * </p>
1230 *
1231 * @param separator the separator to use
1232 * @return this, to enable chaining
1233 */
1234 public TextStringBuilder appendSeparator(final char separator) {
1235 if (isNotEmpty()) {
1236 append(separator);
1237 }
1238 return this;
1239 }
1240
1241 /**
1242 * Appends one of both separators to the builder If the builder is currently empty it will append the
1243 * defaultIfEmpty-separator Otherwise it will append the standard-separator
1244 *
1245 * The separator is appended using {@link #append(char)}.
1246 *
1247 * @param standard the separator if builder is not empty
1248 * @param defaultIfEmpty the separator if builder is empty
1249 * @return this, to enable chaining
1250 */
1251 public TextStringBuilder appendSeparator(final char standard, final char defaultIfEmpty) {
1252 if (isEmpty()) {
1253 append(defaultIfEmpty);
1254 } else {
1255 append(standard);
1256 }
1257 return this;
1258 }
1259
1260 /**
1261 * Appends a separator to the builder if the loop index is greater than zero. The separator is appended using
1262 * {@link #append(char)}.
1263 * <p>
1264 * This method is useful for adding a separator each time around the loop except the first.
1265 * </p>
1266 *
1267 * <pre>
1268 * for (int i = 0; i < list.size(); i++) {
1269 * appendSeparator(",", i);
1270 * append(list.get(i));
1271 * }
1272 * </pre>
1273 *
1274 * <p>
1275 * Note that for this simple example, you should use {@link #appendWithSeparators(Iterable, String)}.
1276 * </p>
1277 *
1278 * @param separator the separator to use
1279 * @param loopIndex the loop index
1280 * @return this, to enable chaining
1281 */
1282 public TextStringBuilder appendSeparator(final char separator, final int loopIndex) {
1283 if (loopIndex > 0) {
1284 append(separator);
1285 }
1286 return this;
1287 }
1288
1289 /**
1290 * Appends a separator if the builder is currently non-empty. Appending a null separator will have no effect. The
1291 * separator is appended using {@link #append(String)}.
1292 * <p>
1293 * This method is useful for adding a separator each time around the loop except the first.
1294 * </p>
1295 *
1296 * <pre>
1297 * for (Iterator it = list.iterator(); it.hasNext();) {
1298 * appendSeparator(",");
1299 * append(it.next());
1300 * }
1301 * </pre>
1302 *
1303 * <p>
1304 * Note that for this simple example, you should use {@link #appendWithSeparators(Iterable, String)}.
1305 * </p>
1306 *
1307 * @param separator the separator to use, null means no separator
1308 * @return this, to enable chaining
1309 */
1310 public TextStringBuilder appendSeparator(final String separator) {
1311 return appendSeparator(separator, null);
1312 }
1313
1314 /**
1315 * Appends a separator to the builder if the loop index is greater than zero. Appending a null separator will have
1316 * no effect. The separator is appended using {@link #append(String)}.
1317 * <p>
1318 * This method is useful for adding a separator each time around the loop except the first.
1319 * </p>
1320 *
1321 * <pre>
1322 * for (int i = 0; i < list.size(); i++) {
1323 * appendSeparator(",", i);
1324 * append(list.get(i));
1325 * }
1326 * </pre>
1327 *
1328 * <p>
1329 * Note that for this simple example, you should use {@link #appendWithSeparators(Iterable, String)}.
1330 * </p>
1331 *
1332 * @param separator the separator to use, null means no separator
1333 * @param loopIndex the loop index
1334 * @return this, to enable chaining
1335 */
1336 public TextStringBuilder appendSeparator(final String separator, final int loopIndex) {
1337 if (separator != null && loopIndex > 0) {
1338 append(separator);
1339 }
1340 return this;
1341 }
1342
1343 /**
1344 * Appends one of both separators to the StrBuilder. If the builder is currently empty, it will append the
1345 * defaultIfEmpty-separator, otherwise it will append the standard-separator.
1346 * <p>
1347 * Appending a null separator will have no effect. The separator is appended using {@link #append(String)}.
1348 * </p>
1349 * <p>
1350 * This method is for example useful for constructing queries
1351 * </p>
1352 *
1353 * <pre>
1354 * StrBuilder whereClause = new StrBuilder();
1355 * if (searchCommand.getPriority() != null) {
1356 * whereClause.appendSeparator(" and", " where");
1357 * whereClause.append(" priority = ?")
1358 * }
1359 * if (searchCommand.getComponent() != null) {
1360 * whereClause.appendSeparator(" and", " where");
1361 * whereClause.append(" component = ?")
1362 * }
1363 * selectClause.append(whereClause)
1364 * </pre>
1365 *
1366 * @param standard the separator if builder is not empty, null means no separator
1367 * @param defaultIfEmpty the separator if builder is empty, null means no separator
1368 * @return this, to enable chaining
1369 */
1370 public TextStringBuilder appendSeparator(final String standard, final String defaultIfEmpty) {
1371 final String str = isEmpty() ? defaultIfEmpty : standard;
1372 if (str != null) {
1373 append(str);
1374 }
1375 return this;
1376 }
1377
1378 /**
1379 * Appends current contents of this {@code StrBuilder} to the provided {@link Appendable}.
1380 * <p>
1381 * This method tries to avoid doing any extra copies of contents.
1382 * </p>
1383 *
1384 * @param appendable the appendable to append data to
1385 * @throws IOException if an I/O error occurs.
1386 * @see #readFrom(Readable)
1387 */
1388 public void appendTo(final Appendable appendable) throws IOException {
1389 if (appendable instanceof Writer) {
1390 ((Writer) appendable).write(buffer, 0, size);
1391 } else if (appendable instanceof StringBuilder) {
1392 ((StringBuilder) appendable).append(buffer, 0, size);
1393 } else if (appendable instanceof StringBuffer) {
1394 ((StringBuffer) appendable).append(buffer, 0, size);
1395 } else if (appendable instanceof CharBuffer) {
1396 ((CharBuffer) appendable).put(buffer, 0, size);
1397 } else {
1398 appendable.append(this);
1399 }
1400 }
1401
1402 /** Appends {@code "true"}. */
1403 private void appendTrue(int index) {
1404 buffer[index++] = 't';
1405 buffer[index++] = 'r';
1406 buffer[index++] = 'u';
1407 buffer[index] = 'e';
1408 size += TRUE_STRING_SIZE;
1409 }
1410
1411 /**
1412 * Appends an iterable placing separators between each value, but not before the first or after the last. Appending
1413 * a null iterable will have no effect. Each object is appended using {@link #append(Object)}.
1414 *
1415 * @param iterable the iterable to append
1416 * @param separator the separator to use, null means no separator
1417 * @return this, to enable chaining
1418 */
1419 public TextStringBuilder appendWithSeparators(final Iterable<?> iterable, final String separator) {
1420 if (iterable != null) {
1421 appendWithSeparators(iterable.iterator(), separator);
1422 }
1423 return this;
1424 }
1425
1426 /**
1427 * Appends an iterator placing separators between each value, but not before the first or after the last. Appending
1428 * a null iterator will have no effect. Each object is appended using {@link #append(Object)}.
1429 *
1430 * @param it the iterator to append
1431 * @param separator the separator to use, null means no separator
1432 * @return this, to enable chaining
1433 */
1434 public TextStringBuilder appendWithSeparators(final Iterator<?> it, final String separator) {
1435 if (it != null) {
1436 final String sep = Objects.toString(separator, StringUtils.EMPTY);
1437 while (it.hasNext()) {
1438 append(it.next());
1439 if (it.hasNext()) {
1440 append(sep);
1441 }
1442 }
1443 }
1444 return this;
1445 }
1446
1447 /**
1448 * Appends an array placing separators between each value, but not before the first or after the last. Appending a
1449 * null array will have no effect. Each object is appended using {@link #append(Object)}.
1450 *
1451 * @param array the array to append
1452 * @param separator the separator to use, null means no separator
1453 * @return this, to enable chaining
1454 */
1455 public TextStringBuilder appendWithSeparators(final Object[] array, final String separator) {
1456 if (array != null && array.length > 0) {
1457 final String sep = Objects.toString(separator, StringUtils.EMPTY);
1458 append(array[0]);
1459 for (int i = 1; i < array.length; i++) {
1460 append(sep);
1461 append(array[i]);
1462 }
1463 }
1464 return this;
1465 }
1466
1467 /**
1468 * Gets the contents of this builder as a Reader.
1469 * <p>
1470 * This method allows the contents of the builder to be read using any standard method that expects a Reader.
1471 * </p>
1472 * <p>
1473 * To use, simply create a {@code StrBuilder}, populate it with data, call {@code asReader}, and then read away.
1474 * </p>
1475 * <p>
1476 * The internal character array is shared between the builder and the reader. This allows you to append to the
1477 * builder after creating the reader, and the changes will be picked up. Note however, that no synchronization
1478 * occurs, so you must perform all operations with the builder and the reader in one thread.
1479 * </p>
1480 * <p>
1481 * The returned reader supports marking, and ignores the flush method.
1482 * </p>
1483 *
1484 * @return a reader that reads from this builder
1485 */
1486 public Reader asReader() {
1487 return new TextStringBuilderReader();
1488 }
1489
1490 /**
1491 * Creates a tokenizer that can tokenize the contents of this builder.
1492 * <p>
1493 * This method allows the contents of this builder to be tokenized. The tokenizer will be setup by default to
1494 * tokenize on space, tab, newline and form feed (as per StringTokenizer). These values can be changed on the
1495 * tokenizer class, before retrieving the tokens.
1496 * </p>
1497 * <p>
1498 * The returned tokenizer is linked to this builder. You may intermix calls to the builder and tokenizer within
1499 * certain limits, however there is no synchronization. Once the tokenizer has been used once, it must be
1500 * {@link StringTokenizer#reset() reset} to pickup the latest changes in the builder. For example:
1501 * </p>
1502 *
1503 * <pre>
1504 * StrBuilder b = new StrBuilder();
1505 * b.append("a b ");
1506 * StrTokenizer t = b.asTokenizer();
1507 * String[] tokens1 = t.getTokenArray(); // returns a,b
1508 * b.append("c d ");
1509 * String[] tokens2 = t.getTokenArray(); // returns a,b (c and d ignored)
1510 * t.reset(); // reset causes builder changes to be picked up
1511 * String[] tokens3 = t.getTokenArray(); // returns a,b,c,d
1512 * </pre>
1513 *
1514 * <p>
1515 * In addition to simply intermixing appends and tokenization, you can also call the set methods on the tokenizer to
1516 * alter how it tokenizes. Just remember to call reset when you want to pickup builder changes.
1517 * </p>
1518 * <p>
1519 * Calling {@link StringTokenizer#reset(String)} or {@link StringTokenizer#reset(char[])} with a non-null value will
1520 * break the link with the builder.
1521 * </p>
1522 *
1523 * @return a tokenizer that is linked to this builder
1524 */
1525 public StringTokenizer asTokenizer() {
1526 return new TextStringBuilderTokenizer();
1527 }
1528
1529 /**
1530 * Gets this builder as a Writer that can be written to.
1531 * <p>
1532 * This method allows you to populate the contents of the builder using any standard method that takes a Writer.
1533 * </p>
1534 * <p>
1535 * To use, simply create a {@code StrBuilder}, call {@code asWriter}, and populate away. The data is available at
1536 * any time using the methods of the {@code StrBuilder}.
1537 * </p>
1538 * <p>
1539 * The internal character array is shared between the builder and the writer. This allows you to intermix calls that
1540 * append to the builder and write using the writer and the changes will be occur correctly. Note however, that no
1541 * synchronization occurs, so you must perform all operations with the builder and the writer in one thread.
1542 * </p>
1543 * <p>
1544 * The returned writer ignores the close and flush methods.
1545 * </p>
1546 *
1547 * @return a writer that populates this builder
1548 */
1549 public Writer asWriter() {
1550 return new TextStringBuilderWriter();
1551 }
1552
1553 /**
1554 * Converts this instance to a String.
1555 *
1556 * @return This instance as a String
1557 * @see #toString()
1558 * @deprecated Use {@link #get()}.
1559 */
1560 @Deprecated
1561 @Override
1562 public String build() {
1563 return toString();
1564 }
1565
1566 /**
1567 * Gets the current size of the internal character array buffer.
1568 *
1569 * @return The capacity
1570 */
1571 public int capacity() {
1572 return buffer.length;
1573 }
1574
1575 /**
1576 * Gets the character at the specified index.
1577 *
1578 * @see #setCharAt(int, char)
1579 * @see #deleteCharAt(int)
1580 * @param index the index to retrieve, must be valid
1581 * @return The character at the index
1582 * @throws IndexOutOfBoundsException if the index is invalid
1583 */
1584 @Override
1585 public char charAt(final int index) {
1586 validateIndex(index);
1587 return buffer[index];
1588 }
1589
1590 /**
1591 * Clears the string builder (convenience Collections API style method).
1592 * <p>
1593 * This method does not reduce the size of the internal character buffer. To do that, call {@code clear()} followed
1594 * by {@link #minimizeCapacity()}.
1595 * </p>
1596 * <p>
1597 * This method is the same as {@link #setLength(int)} called with zero and is provided to match the API of
1598 * Collections.
1599 * </p>
1600 *
1601 * @return this, to enable chaining
1602 */
1603 public TextStringBuilder clear() {
1604 size = 0;
1605 return this;
1606 }
1607
1608 /**
1609 * Tests if the string builder contains the specified char.
1610 *
1611 * @param ch the character to find
1612 * @return true if the builder contains the character
1613 */
1614 public boolean contains(final char ch) {
1615 final char[] thisBuf = buffer;
1616 for (int i = 0; i < this.size; i++) {
1617 if (thisBuf[i] == ch) {
1618 return true;
1619 }
1620 }
1621 return false;
1622 }
1623
1624 /**
1625 * Tests if the string builder contains the specified string.
1626 *
1627 * @param str the string to find
1628 * @return true if the builder contains the string
1629 */
1630 public boolean contains(final String str) {
1631 return indexOf(str, 0) >= 0;
1632 }
1633
1634 /**
1635 * Tests if the string builder contains a string matched using the specified matcher.
1636 * <p>
1637 * Matchers can be used to perform advanced searching behavior. For example you could write a matcher to search for
1638 * the character 'a' followed by a number.
1639 * </p>
1640 *
1641 * @param matcher the matcher to use, null returns -1
1642 * @return true if the matcher finds a match in the builder
1643 */
1644 public boolean contains(final StringMatcher matcher) {
1645 return indexOf(matcher, 0) >= 0;
1646 }
1647
1648 /**
1649 * Deletes the characters between the two specified indices.
1650 *
1651 * @param startIndex the start index, inclusive, must be valid
1652 * @param endIndex the end index, exclusive, must be valid except that if too large it is treated as end of string
1653 * @return this, to enable chaining
1654 * @throws IndexOutOfBoundsException if the index is invalid
1655 */
1656 public TextStringBuilder delete(final int startIndex, final int endIndex) {
1657 final int actualEndIndex = validateRange(startIndex, endIndex);
1658 final int len = actualEndIndex - startIndex;
1659 if (len > 0) {
1660 deleteImpl(startIndex, actualEndIndex, len);
1661 }
1662 return this;
1663 }
1664
1665 /**
1666 * Deletes the character wherever it occurs in the builder.
1667 *
1668 * @param ch the character to delete
1669 * @return this, to enable chaining
1670 */
1671 public TextStringBuilder deleteAll(final char ch) {
1672 for (int i = 0; i < size; i++) {
1673 if (buffer[i] == ch) {
1674 final int start = i;
1675 while (++i < size) {
1676 if (buffer[i] != ch) {
1677 break;
1678 }
1679 }
1680 final int len = i - start;
1681 deleteImpl(start, i, len);
1682 i -= len;
1683 }
1684 }
1685 return this;
1686 }
1687
1688 /**
1689 * Deletes the string wherever it occurs in the builder.
1690 *
1691 * @param str the string to delete, null causes no action
1692 * @return this, to enable chaining
1693 */
1694 public TextStringBuilder deleteAll(final String str) {
1695 final int len = str == null ? 0 : str.length();
1696 if (len > 0) {
1697 int index = indexOf(str, 0);
1698 while (index >= 0) {
1699 deleteImpl(index, index + len, len);
1700 index = indexOf(str, index);
1701 }
1702 }
1703 return this;
1704 }
1705
1706 /**
1707 * Deletes all parts of the builder that the matcher matches.
1708 * <p>
1709 * Matchers can be used to perform advanced deletion behavior. For example you could write a matcher to delete all
1710 * occurrences where the character 'a' is followed by a number.
1711 * </p>
1712 *
1713 * @param matcher the matcher to use to find the deletion, null causes no action
1714 * @return this, to enable chaining
1715 */
1716 public TextStringBuilder deleteAll(final StringMatcher matcher) {
1717 return replace(matcher, null, 0, size, -1);
1718 }
1719
1720 /**
1721 * Deletes the character at the specified index.
1722 *
1723 * @see #charAt(int)
1724 * @see #setCharAt(int, char)
1725 * @param index the index to delete
1726 * @return this, to enable chaining
1727 * @throws IndexOutOfBoundsException if the index is invalid
1728 */
1729 public TextStringBuilder deleteCharAt(final int index) {
1730 validateIndex(index);
1731 deleteImpl(index, index + 1, 1);
1732 return this;
1733 }
1734
1735 /**
1736 * Deletes the character wherever it occurs in the builder.
1737 *
1738 * @param ch the character to delete
1739 * @return this, to enable chaining
1740 */
1741 public TextStringBuilder deleteFirst(final char ch) {
1742 for (int i = 0; i < size; i++) {
1743 if (buffer[i] == ch) {
1744 deleteImpl(i, i + 1, 1);
1745 break;
1746 }
1747 }
1748 return this;
1749 }
1750
1751 /**
1752 * Deletes the string wherever it occurs in the builder.
1753 *
1754 * @param str the string to delete, null causes no action
1755 * @return this, to enable chaining
1756 */
1757 public TextStringBuilder deleteFirst(final String str) {
1758 final int len = str == null ? 0 : str.length();
1759 if (len > 0) {
1760 final int index = indexOf(str, 0);
1761 if (index >= 0) {
1762 deleteImpl(index, index + len, len);
1763 }
1764 }
1765 return this;
1766 }
1767
1768 /**
1769 * Deletes the first match within the builder using the specified matcher.
1770 * <p>
1771 * Matchers can be used to perform advanced deletion behavior. For example you could write a matcher to delete where
1772 * the character 'a' is followed by a number.
1773 * </p>
1774 *
1775 * @param matcher the matcher to use to find the deletion, null causes no action
1776 * @return this, to enable chaining
1777 */
1778 public TextStringBuilder deleteFirst(final StringMatcher matcher) {
1779 return replace(matcher, null, 0, size, 1);
1780 }
1781
1782 /**
1783 * Internal method to delete a range without validation.
1784 *
1785 * @param startIndex the start index, must be valid
1786 * @param endIndex the end index (exclusive), must be valid
1787 * @param len the length, must be valid
1788 * @throws IndexOutOfBoundsException if any index is invalid
1789 */
1790 private void deleteImpl(final int startIndex, final int endIndex, final int len) {
1791 System.arraycopy(buffer, endIndex, buffer, startIndex, size - endIndex);
1792 size -= len;
1793 }
1794
1795 /**
1796 * Gets the character at the specified index before deleting it.
1797 *
1798 * @see #charAt(int)
1799 * @see #deleteCharAt(int)
1800 * @param index the index to retrieve, must be valid
1801 * @return The character at the index
1802 * @throws IndexOutOfBoundsException if the index is invalid
1803 * @since 1.9
1804 */
1805 public char drainChar(final int index) {
1806 validateIndex(index);
1807 final char c = buffer[index];
1808 deleteCharAt(index);
1809 return c;
1810 }
1811
1812 /**
1813 * Drains (copies, then deletes) this character sequence into the specified array. This is equivalent to copying the
1814 * characters from this sequence into the target and then deleting those character from this sequence.
1815 *
1816 * @param startIndex first index to copy, inclusive.
1817 * @param endIndex last index to copy, exclusive.
1818 * @param target the target array, must not be {@code null}.
1819 * @param targetIndex the index to start copying in the target.
1820 * @return How many characters where copied (then deleted). If this builder is empty, return {@code 0}.
1821 * @since 1.9
1822 */
1823 public int drainChars(final int startIndex, final int endIndex, final char[] target, final int targetIndex) {
1824 final int length = endIndex - startIndex;
1825 if (isEmpty() || length == 0 || target.length == 0) {
1826 return 0;
1827 }
1828 final int actualLen = Math.min(Math.min(size, length), target.length - targetIndex);
1829 getChars(startIndex, actualLen, target, targetIndex);
1830 delete(startIndex, actualLen);
1831 return actualLen;
1832 }
1833
1834 /**
1835 * Checks whether this builder ends with the specified string.
1836 * <p>
1837 * Note that this method handles null input quietly, unlike String.
1838 * </p>
1839 *
1840 * @param str the string to search for, null returns false
1841 * @return true if the builder ends with the string
1842 */
1843 public boolean endsWith(final String str) {
1844 if (str == null) {
1845 return false;
1846 }
1847 final int len = str.length();
1848 if (len == 0) {
1849 return true;
1850 }
1851 if (len > size) {
1852 return false;
1853 }
1854 int pos = size - len;
1855 for (int i = 0; i < len; i++, pos++) {
1856 if (buffer[pos] != str.charAt(i)) {
1857 return false;
1858 }
1859 }
1860 return true;
1861 }
1862
1863 /**
1864 * Tests the capacity and ensures that it is at least the size specified.
1865 *
1866 * <p>
1867 * Note: This method can be used to minimise memory reallocations during
1868 * repeated addition of values by pre-allocating the character buffer.
1869 * The method ignores a negative {@code capacity} argument.
1870 * </p>
1871 *
1872 * @param capacity the capacity to ensure
1873 * @return this, to enable chaining
1874 * @throws OutOfMemoryError if the capacity cannot be allocated
1875 */
1876 public TextStringBuilder ensureCapacity(final int capacity) {
1877 if (capacity > 0) {
1878 ensureCapacityInternal(capacity);
1879 }
1880 return this;
1881 }
1882
1883 /**
1884 * Ensures that the buffer is at least the size specified. The {@code capacity} argument
1885 * is treated as an unsigned integer.
1886 *
1887 * <p>
1888 * This method will raise an {@link OutOfMemoryError} if the capacity is too large
1889 * for an array, or cannot be allocated.
1890 * </p>
1891 *
1892 * @param capacity the capacity to ensure
1893 * @throws OutOfMemoryError if the capacity cannot be allocated
1894 */
1895 private void ensureCapacityInternal(final int capacity) {
1896 // Check for overflow of the current buffer.
1897 // Assumes capacity is an unsigned integer up to Integer.MAX_VALUE * 2
1898 // (the largest possible addition of two maximum length arrays).
1899 if (capacity - buffer.length > 0) {
1900 resizeBuffer(capacity);
1901 }
1902 }
1903
1904 /**
1905 * Tests the contents of this builder against another to see if they contain the same character content.
1906 *
1907 * @param obj the object to check, null returns false
1908 * @return true if the builders contain the same characters in the same order
1909 */
1910 @Override
1911 public boolean equals(final Object obj) {
1912 return obj instanceof TextStringBuilder && equals((TextStringBuilder) obj);
1913 }
1914
1915 /**
1916 * Tests the contents of this builder against another to see if they contain the same character content.
1917 *
1918 * @param other the object to check, null returns false
1919 * @return true if the builders contain the same characters in the same order
1920 */
1921 public boolean equals(final TextStringBuilder other) {
1922 if (this == other) {
1923 return true;
1924 }
1925 if (other == null) {
1926 return false;
1927 }
1928 if (this.size != other.size) {
1929 return false;
1930 }
1931 // Be aware not to use Arrays.equals(buffer, other.buffer) for equals() method
1932 // as length of the buffers may be different (TEXT-211)
1933 final char[] thisBuf = this.buffer;
1934 final char[] otherBuf = other.buffer;
1935 for (int i = size - 1; i >= 0; i--) {
1936 if (thisBuf[i] != otherBuf[i]) {
1937 return false;
1938 }
1939 }
1940 return true;
1941 }
1942
1943 /**
1944 * Tests the contents of this builder against another to see if they contain the same character content ignoring
1945 * case.
1946 *
1947 * @param other the object to check, null returns false
1948 * @return true if the builders contain the same characters in the same order
1949 */
1950 public boolean equalsIgnoreCase(final TextStringBuilder other) {
1951 if (this == other) {
1952 return true;
1953 }
1954 if (this.size != other.size) {
1955 return false;
1956 }
1957 final char[] thisBuf = this.buffer;
1958 final char[] otherBuf = other.buffer;
1959 for (int i = size - 1; i >= 0; i--) {
1960 final char c1 = thisBuf[i];
1961 final char c2 = otherBuf[i];
1962 if (c1 != c2 && Character.toUpperCase(c1) != Character.toUpperCase(c2)) {
1963 return false;
1964 }
1965 }
1966 return true;
1967 }
1968
1969 /**
1970 * Converts this instance to a String.
1971 *
1972 * @return This instance as a String
1973 * @see #toString()
1974 * @since 1.12.0
1975 */
1976 @Override
1977 public String get() {
1978 return toString();
1979 }
1980
1981 /**
1982 * Gets a direct reference to internal storage, not for public consumption.
1983 */
1984 char[] getBuffer() {
1985 return buffer;
1986 }
1987
1988 /**
1989 * Copies this character array into the specified array.
1990 *
1991 * @param target the target array, null will cause an array to be created
1992 * @return The input array, unless that was null or too small
1993 */
1994 public char[] getChars(char[] target) {
1995 final int len = length();
1996 if (target == null || target.length < len) {
1997 target = new char[len];
1998 }
1999 System.arraycopy(buffer, 0, target, 0, len);
2000 return target;
2001 }
2002
2003 /**
2004 * Copies this character array into the specified array.
2005 *
2006 * @param startIndex first index to copy, inclusive, must be valid.
2007 * @param endIndex last index to copy, exclusive, must be valid.
2008 * @param target the target array, must not be null or too small.
2009 * @param targetIndex the index to start copying in target.
2010 * @throws NullPointerException if the array is null.
2011 * @throws IndexOutOfBoundsException if any index is invalid.
2012 */
2013 public void getChars(final int startIndex, final int endIndex, final char[] target, final int targetIndex) {
2014 if (startIndex < 0) {
2015 throw new StringIndexOutOfBoundsException(startIndex);
2016 }
2017 if (endIndex < 0 || endIndex > length()) {
2018 throw new StringIndexOutOfBoundsException(endIndex);
2019 }
2020 if (startIndex > endIndex) {
2021 throw new StringIndexOutOfBoundsException("end < start");
2022 }
2023 System.arraycopy(buffer, startIndex, target, targetIndex, endIndex - startIndex);
2024 }
2025
2026 /**
2027 * Gets the text to be appended when a {@link #appendNewLine() new line} is added.
2028 *
2029 * @return The new line text, {@code null} means use the system default from {@link System#lineSeparator()}.
2030 */
2031 public String getNewLineText() {
2032 return newLine;
2033 }
2034
2035 /**
2036 * Gets the text to be appended when null is added.
2037 *
2038 * @return The null text, null means no append
2039 */
2040 public String getNullText() {
2041 return nullText;
2042 }
2043
2044 /**
2045 * Gets a suitable hash code for this builder.
2046 *
2047 * @return a hash code
2048 */
2049 @Override
2050 public int hashCode() {
2051 // no allocation
2052 final char[] buf = buffer;
2053 int result = 0;
2054 for (int i = 0; i < size; i++) {
2055 result = 31 * result + buf[i];
2056 }
2057 return result;
2058 }
2059
2060 /**
2061 * Searches the string builder to find the first reference to the specified char.
2062 *
2063 * @param ch the character to find
2064 * @return The first index of the character, or -1 if not found
2065 */
2066 public int indexOf(final char ch) {
2067 return indexOf(ch, 0);
2068 }
2069
2070 /**
2071 * Searches the string builder to find the first reference to the specified char.
2072 *
2073 * @param ch the character to find
2074 * @param startIndex the index to start at, invalid index rounded to edge
2075 * @return The first index of the character, or -1 if not found
2076 */
2077 public int indexOf(final char ch, int startIndex) {
2078 startIndex = Math.max(0, startIndex);
2079 if (startIndex >= size) {
2080 return StringUtils.INDEX_NOT_FOUND;
2081 }
2082 final char[] thisBuf = buffer;
2083 for (int i = startIndex; i < size; i++) {
2084 if (thisBuf[i] == ch) {
2085 return i;
2086 }
2087 }
2088 return StringUtils.INDEX_NOT_FOUND;
2089 }
2090
2091 /**
2092 * Searches the string builder to find the first reference to the specified string.
2093 * <p>
2094 * Note that a null input string will return -1, whereas the JDK throws an exception.
2095 * </p>
2096 *
2097 * @param str the string to find, null returns -1
2098 * @return The first index of the string, or -1 if not found
2099 */
2100 public int indexOf(final String str) {
2101 return indexOf(str, 0);
2102 }
2103
2104 /**
2105 * Searches the string builder to find the first reference to the specified string starting searching from the given
2106 * index.
2107 * <p>
2108 * Note that a null input string will return -1, whereas the JDK throws an exception.
2109 * </p>
2110 *
2111 * @param str the string to find, null returns -1
2112 * @param startIndex the index to start at, invalid index rounded to edge
2113 * @return The first index of the string, or -1 if not found
2114 */
2115 public int indexOf(final String str, int startIndex) {
2116 startIndex = Math.max(0, startIndex);
2117 if (str == null || startIndex >= size) {
2118 return StringUtils.INDEX_NOT_FOUND;
2119 }
2120 final int strLen = str.length();
2121 if (strLen == 1) {
2122 return indexOf(str.charAt(0), startIndex);
2123 }
2124 if (strLen == 0) {
2125 return startIndex;
2126 }
2127 if (strLen > size) {
2128 return StringUtils.INDEX_NOT_FOUND;
2129 }
2130 final char[] thisBuf = buffer;
2131 final int searchLen = size - strLen + 1;
2132 for (int i = startIndex; i < searchLen; i++) {
2133 boolean found = true;
2134 for (int j = 0; j < strLen && found; j++) {
2135 found = str.charAt(j) == thisBuf[i + j];
2136 }
2137 if (found) {
2138 return i;
2139 }
2140 }
2141 return StringUtils.INDEX_NOT_FOUND;
2142 }
2143
2144 /**
2145 * Searches the string builder using the matcher to find the first match.
2146 * <p>
2147 * Matchers can be used to perform advanced searching behavior. For example you could write a matcher to find the
2148 * character 'a' followed by a number.
2149 * </p>
2150 *
2151 * @param matcher the matcher to use, null returns -1
2152 * @return The first index matched, or -1 if not found
2153 */
2154 public int indexOf(final StringMatcher matcher) {
2155 return indexOf(matcher, 0);
2156 }
2157
2158 /**
2159 * Searches the string builder using the matcher to find the first match searching from the given index.
2160 * <p>
2161 * Matchers can be used to perform advanced searching behavior. For example you could write a matcher to find the
2162 * character 'a' followed by a number.
2163 * </p>
2164 *
2165 * @param matcher the matcher to use, null returns -1
2166 * @param startIndex the index to start at, invalid index rounded to edge
2167 * @return The first index matched, or -1 if not found
2168 */
2169 public int indexOf(final StringMatcher matcher, int startIndex) {
2170 startIndex = Math.max(0, startIndex);
2171 if (matcher == null || startIndex >= size) {
2172 return StringUtils.INDEX_NOT_FOUND;
2173 }
2174 final int len = size;
2175 final char[] buf = buffer;
2176 for (int i = startIndex; i < len; i++) {
2177 if (matcher.isMatch(buf, i, startIndex, len) > 0) {
2178 return i;
2179 }
2180 }
2181 return StringUtils.INDEX_NOT_FOUND;
2182 }
2183
2184 /**
2185 * Inserts the value into this builder.
2186 *
2187 * @param index the index to add at, must be valid
2188 * @param value the value to insert
2189 * @return this, to enable chaining
2190 * @throws IndexOutOfBoundsException if the index is invalid
2191 */
2192 public TextStringBuilder insert(final int index, final boolean value) {
2193 validateIndex(index);
2194 if (value) {
2195 ensureCapacityInternal(size + TRUE_STRING_SIZE);
2196 System.arraycopy(buffer, index, buffer, index + TRUE_STRING_SIZE, size - index);
2197 appendTrue(index);
2198 } else {
2199 ensureCapacityInternal(size + FALSE_STRING_SIZE);
2200 System.arraycopy(buffer, index, buffer, index + FALSE_STRING_SIZE, size - index);
2201 appendFalse(index);
2202 }
2203 return this;
2204 }
2205
2206 /**
2207 * Inserts the value into this builder.
2208 *
2209 * @param index the index to add at, must be valid
2210 * @param value the value to insert
2211 * @return this, to enable chaining
2212 * @throws IndexOutOfBoundsException if the index is invalid
2213 */
2214 public TextStringBuilder insert(final int index, final char value) {
2215 validateIndex(index);
2216 ensureCapacityInternal(size + 1);
2217 System.arraycopy(buffer, index, buffer, index + 1, size - index);
2218 buffer[index] = value;
2219 size++;
2220 return this;
2221 }
2222
2223 /**
2224 * Inserts the character array into this builder. Inserting null will use the stored null text value.
2225 *
2226 * @param index the index to add at, must be valid
2227 * @param chars the char array to insert
2228 * @return this, to enable chaining
2229 * @throws IndexOutOfBoundsException if the index is invalid
2230 */
2231 public TextStringBuilder insert(final int index, final char[] chars) {
2232 validateIndex(index);
2233 if (chars == null) {
2234 return insert(index, nullText);
2235 }
2236 final int len = chars.length;
2237 if (len > 0) {
2238 ensureCapacityInternal(size + len);
2239 System.arraycopy(buffer, index, buffer, index + len, size - index);
2240 System.arraycopy(chars, 0, buffer, index, len);
2241 size += len;
2242 }
2243 return this;
2244 }
2245
2246 /**
2247 * Inserts part of the character array into this builder. Inserting null will use the stored null text value.
2248 *
2249 * @param index the index to add at, must be valid
2250 * @param chars the char array to insert
2251 * @param offset the offset into the character array to start at, must be valid
2252 * @param length the length of the character array part to copy, must be positive
2253 * @return this, to enable chaining
2254 * @throws IndexOutOfBoundsException if any index is invalid
2255 */
2256 public TextStringBuilder insert(final int index, final char[] chars, final int offset, final int length) {
2257 validateIndex(index);
2258 if (chars == null) {
2259 return insert(index, nullText);
2260 }
2261 if (offset < 0 || offset > chars.length) {
2262 throw new StringIndexOutOfBoundsException("Invalid offset: " + offset);
2263 }
2264 if (length < 0 || offset + length > chars.length) {
2265 throw new StringIndexOutOfBoundsException("Invalid length: " + length);
2266 }
2267 if (length > 0) {
2268 ensureCapacityInternal(size + length);
2269 System.arraycopy(buffer, index, buffer, index + length, size - index);
2270 System.arraycopy(chars, offset, buffer, index, length);
2271 size += length;
2272 }
2273 return this;
2274 }
2275
2276 /**
2277 * Inserts the value into this builder.
2278 *
2279 * @param index the index to add at, must be valid
2280 * @param value the value to insert
2281 * @return this, to enable chaining
2282 * @throws IndexOutOfBoundsException if the index is invalid
2283 */
2284 public TextStringBuilder insert(final int index, final double value) {
2285 return insert(index, String.valueOf(value));
2286 }
2287
2288 /**
2289 * Inserts the value into this builder.
2290 *
2291 * @param index the index to add at, must be valid
2292 * @param value the value to insert
2293 * @return this, to enable chaining
2294 * @throws IndexOutOfBoundsException if the index is invalid
2295 */
2296 public TextStringBuilder insert(final int index, final float value) {
2297 return insert(index, String.valueOf(value));
2298 }
2299
2300 /**
2301 * Inserts the value into this builder.
2302 *
2303 * @param index the index to add at, must be valid
2304 * @param value the value to insert
2305 * @return this, to enable chaining
2306 * @throws IndexOutOfBoundsException if the index is invalid
2307 */
2308 public TextStringBuilder insert(final int index, final int value) {
2309 return insert(index, String.valueOf(value));
2310 }
2311
2312 /**
2313 * Inserts the value into this builder.
2314 *
2315 * @param index the index to add at, must be valid
2316 * @param value the value to insert
2317 * @return this, to enable chaining
2318 * @throws IndexOutOfBoundsException if the index is invalid
2319 */
2320 public TextStringBuilder insert(final int index, final long value) {
2321 return insert(index, String.valueOf(value));
2322 }
2323
2324 /**
2325 * Inserts the string representation of an object into this builder. Inserting null will use the stored null text
2326 * value.
2327 *
2328 * @param index the index to add at, must be valid
2329 * @param obj the object to insert
2330 * @return this, to enable chaining
2331 * @throws IndexOutOfBoundsException if the index is invalid
2332 */
2333 public TextStringBuilder insert(final int index, final Object obj) {
2334 if (obj == null) {
2335 return insert(index, nullText);
2336 }
2337 return insert(index, obj.toString());
2338 }
2339
2340 /**
2341 * Inserts the string into this builder. Inserting null will use the stored null text value.
2342 *
2343 * @param index the index to add at, must be valid
2344 * @param str the string to insert
2345 * @return this, to enable chaining
2346 * @throws IndexOutOfBoundsException if the index is invalid
2347 */
2348 public TextStringBuilder insert(final int index, String str) {
2349 validateIndex(index);
2350 if (str == null) {
2351 str = nullText;
2352 }
2353 if (str != null) {
2354 final int strLen = str.length();
2355 if (strLen > 0) {
2356 final int newSize = size + strLen;
2357 ensureCapacityInternal(newSize);
2358 System.arraycopy(buffer, index, buffer, index + strLen, size - index);
2359 size = newSize;
2360 str.getChars(0, strLen, buffer, index);
2361 }
2362 }
2363 return this;
2364 }
2365
2366 /**
2367 * Checks is the string builder is empty (convenience Collections API style method).
2368 * <p>
2369 * This method is the same as checking {@link #length()} and is provided to match the API of Collections.
2370 * </p>
2371 *
2372 * @return {@code true} if the size is {@code 0}.
2373 */
2374 public boolean isEmpty() {
2375 return size == 0;
2376 }
2377
2378 /**
2379 * Checks is the string builder is not empty.
2380 * <p>
2381 * This method is the same as checking {@link #length()}.
2382 * </p>
2383 *
2384 * @return {@code true} if the size is not {@code 0}.
2385 * @since 1.9
2386 */
2387 public boolean isNotEmpty() {
2388 return size != 0;
2389 }
2390
2391 /**
2392 * Gets whether the internal buffer has been reallocated.
2393 *
2394 * @return Whether the internal buffer has been reallocated.
2395 * @since 1.9
2396 */
2397 public boolean isReallocated() {
2398 return reallocations > 0;
2399 }
2400
2401 /**
2402 * Searches the string builder to find the last reference to the specified char.
2403 *
2404 * @param ch the character to find
2405 * @return The last index of the character, or -1 if not found
2406 */
2407 public int lastIndexOf(final char ch) {
2408 return lastIndexOf(ch, size - 1);
2409 }
2410
2411 /**
2412 * Searches the string builder to find the last reference to the specified char.
2413 *
2414 * @param ch the character to find
2415 * @param startIndex the index to start at, invalid index rounded to edge
2416 * @return The last index of the character, or -1 if not found
2417 */
2418 public int lastIndexOf(final char ch, int startIndex) {
2419 startIndex = startIndex >= size ? size - 1 : startIndex;
2420 if (startIndex < 0) {
2421 return StringUtils.INDEX_NOT_FOUND;
2422 }
2423 for (int i = startIndex; i >= 0; i--) {
2424 if (buffer[i] == ch) {
2425 return i;
2426 }
2427 }
2428 return StringUtils.INDEX_NOT_FOUND;
2429 }
2430
2431 /**
2432 * Searches the string builder to find the last reference to the specified string.
2433 * <p>
2434 * Note that a null input string will return -1, whereas the JDK throws an exception.
2435 * </p>
2436 *
2437 * @param str the string to find, null returns -1
2438 * @return The last index of the string, or -1 if not found
2439 */
2440 public int lastIndexOf(final String str) {
2441 return lastIndexOf(str, size - 1);
2442 }
2443
2444 /**
2445 * Searches the string builder to find the last reference to the specified string starting searching from the given
2446 * index.
2447 * <p>
2448 * Note that a null input string will return -1, whereas the JDK throws an exception.
2449 * </p>
2450 *
2451 * @param str the string to find, null returns -1
2452 * @param startIndex the index to start at, invalid index rounded to edge
2453 * @return The last index of the string, or -1 if not found
2454 */
2455 public int lastIndexOf(final String str, int startIndex) {
2456 startIndex = startIndex >= size ? size - 1 : startIndex;
2457 if (str == null || startIndex < 0) {
2458 return StringUtils.INDEX_NOT_FOUND;
2459 }
2460 final int strLen = str.length();
2461 if (strLen == 0) {
2462 return startIndex;
2463 }
2464 if (strLen > size) {
2465 return StringUtils.INDEX_NOT_FOUND;
2466 }
2467 if (strLen == 1) {
2468 return lastIndexOf(str.charAt(0), startIndex);
2469 }
2470 for (int i = startIndex - strLen + 1; i >= 0; i--) {
2471 boolean found = true;
2472 for (int j = 0; j < strLen && found; j++) {
2473 found = str.charAt(j) == buffer[i + j];
2474 }
2475 if (found) {
2476 return i;
2477 }
2478 }
2479 return StringUtils.INDEX_NOT_FOUND;
2480 }
2481
2482 /**
2483 * Searches the string builder using the matcher to find the last match.
2484 * <p>
2485 * Matchers can be used to perform advanced searching behavior. For example you could write a matcher to find the
2486 * character 'a' followed by a number.
2487 * </p>
2488 *
2489 * @param matcher the matcher to use, null returns -1
2490 * @return The last index matched, or -1 if not found
2491 */
2492 public int lastIndexOf(final StringMatcher matcher) {
2493 return lastIndexOf(matcher, size);
2494 }
2495
2496 /**
2497 * Searches the string builder using the matcher to find the last match searching from the given index.
2498 * <p>
2499 * Matchers can be used to perform advanced searching behavior. For example you could write a matcher to find the
2500 * character 'a' followed by a number.
2501 * </p>
2502 *
2503 * @param matcher the matcher to use, null returns -1
2504 * @param startIndex the index to start at, invalid index rounded to edge
2505 * @return The last index matched, or -1 if not found
2506 */
2507 public int lastIndexOf(final StringMatcher matcher, int startIndex) {
2508 startIndex = startIndex >= size ? size - 1 : startIndex;
2509 if (matcher == null || startIndex < 0) {
2510 return StringUtils.INDEX_NOT_FOUND;
2511 }
2512 final char[] buf = buffer;
2513 final int endIndex = startIndex + 1;
2514 for (int i = startIndex; i >= 0; i--) {
2515 if (matcher.isMatch(buf, i, 0, endIndex) > 0) {
2516 return i;
2517 }
2518 }
2519 return StringUtils.INDEX_NOT_FOUND;
2520 }
2521
2522 /**
2523 * Extracts the leftmost characters from the string builder without throwing an exception.
2524 * <p>
2525 * This method extracts the left {@code length} characters from the builder. If this many characters are not
2526 * available, the whole builder is returned. Thus the returned string may be shorter than the length requested.
2527 * </p>
2528 *
2529 * @param length the number of characters to extract, negative returns empty string
2530 * @return The new string
2531 */
2532 public String leftString(final int length) {
2533 if (length <= 0) {
2534 return StringUtils.EMPTY;
2535 }
2536 if (length >= size) {
2537 return new String(buffer, 0, size);
2538 }
2539 return new String(buffer, 0, length);
2540 }
2541
2542 /**
2543 * Gets the length of the string builder.
2544 *
2545 * @return The length
2546 */
2547 @Override
2548 public int length() {
2549 return size;
2550 }
2551
2552 /**
2553 * Extracts some characters from the middle of the string builder without throwing an exception.
2554 * <p>
2555 * This method extracts {@code length} characters from the builder at the specified index. If the index is negative
2556 * it is treated as zero. If the index is greater than the builder size, it is treated as the builder size. If the
2557 * length is negative, the empty string is returned. If insufficient characters are available in the builder, as
2558 * much as possible is returned. Thus the returned string may be shorter than the length requested.
2559 * </p>
2560 *
2561 * @param index the index to start at, negative means zero
2562 * @param length the number of characters to extract, negative returns empty string
2563 * @return The new string
2564 */
2565 public String midString(int index, final int length) {
2566 if (index < 0) {
2567 index = 0;
2568 }
2569 if (length <= 0 || index >= size) {
2570 return StringUtils.EMPTY;
2571 }
2572 if (size <= index + length) {
2573 return new String(buffer, index, size - index);
2574 }
2575 return new String(buffer, index, length);
2576 }
2577
2578 /**
2579 * Minimizes the capacity to the actual length of the string.
2580 *
2581 * @return this, to enable chaining
2582 */
2583 public TextStringBuilder minimizeCapacity() {
2584 if (buffer.length > size) {
2585 reallocate(size);
2586 }
2587 return this;
2588 }
2589
2590 /**
2591 * If possible, reads chars from the provided {@link CharBuffer} directly into underlying character buffer without
2592 * making extra copies.
2593 *
2594 * @param charBuffer CharBuffer to read.
2595 * @return The number of characters read.
2596 * @see #appendTo(Appendable)
2597 * @since 1.9
2598 */
2599 public int readFrom(final CharBuffer charBuffer) {
2600 final int oldSize = size;
2601 final int remaining = charBuffer.remaining();
2602 ensureCapacityInternal(size + remaining);
2603 charBuffer.get(buffer, size, remaining);
2604 size += remaining;
2605 return size - oldSize;
2606 }
2607
2608 /**
2609 * If possible, reads all chars from the provided {@link Readable} directly into underlying character buffer without
2610 * making extra copies.
2611 *
2612 * @param readable object to read from
2613 * @return The number of characters read
2614 * @throws IOException if an I/O error occurs.
2615 * @see #appendTo(Appendable)
2616 */
2617 public int readFrom(final Readable readable) throws IOException {
2618 if (readable instanceof Reader) {
2619 return readFrom((Reader) readable);
2620 }
2621 if (readable instanceof CharBuffer) {
2622 return readFrom((CharBuffer) readable);
2623 }
2624 final int oldSize = size;
2625 while (true) {
2626 ensureCapacityInternal(size + 1);
2627 final CharBuffer buf = CharBuffer.wrap(buffer, size, buffer.length - size);
2628 final int read = readable.read(buf);
2629 if (read == EOS) {
2630 break;
2631 }
2632 size += read;
2633 }
2634 return size - oldSize;
2635 }
2636
2637 /**
2638 * If possible, reads all chars from the provided {@link Reader} directly into underlying character buffer without
2639 * making extra copies.
2640 *
2641 * @param reader Reader to read.
2642 * @return The number of characters read or -1 if we reached the end of stream.
2643 * @throws IOException if an I/O error occurs.
2644 * @see #appendTo(Appendable)
2645 * @since 1.9
2646 */
2647 public int readFrom(final Reader reader) throws IOException {
2648 final int oldSize = size;
2649 ensureCapacityInternal(size + 1);
2650 int readCount = reader.read(buffer, size, buffer.length - size);
2651 if (readCount == EOS) {
2652 return EOS;
2653 }
2654 do {
2655 size += readCount;
2656 ensureCapacityInternal(size + 1);
2657 readCount = reader.read(buffer, size, buffer.length - size);
2658 } while (readCount != EOS);
2659 return size - oldSize;
2660 }
2661
2662 /**
2663 * If possible, reads {@code count} chars from the provided {@link Reader} directly into underlying character buffer
2664 * without making extra copies.
2665 *
2666 * @param reader Reader to read.
2667 * @param count The maximum characters to read, a value <= 0 returns 0.
2668 * @return The number of characters read. If less than {@code count}, then we've reached the end-of-stream, or -1 if
2669 * we reached the end of stream.
2670 * @throws IOException if an I/O error occurs.
2671 * @see #appendTo(Appendable)
2672 * @since 1.9
2673 */
2674 public int readFrom(final Reader reader, final int count) throws IOException {
2675 if (count <= 0) {
2676 return 0;
2677 }
2678 final int oldSize = size;
2679 ensureCapacityInternal(size + count);
2680 int target = count;
2681 int readCount = reader.read(buffer, size, target);
2682 if (readCount == EOS) {
2683 return EOS;
2684 }
2685 do {
2686 target -= readCount;
2687 size += readCount;
2688 readCount = reader.read(buffer, size, target);
2689 } while (target > 0 && readCount != EOS);
2690 return size - oldSize;
2691 }
2692
2693 /**
2694 * Reallocates the buffer to the new length.
2695 *
2696 * @param newLength the length of the copy to be returned
2697 */
2698 private void reallocate(final int newLength) {
2699 this.buffer = Arrays.copyOf(buffer, newLength);
2700 this.reallocations++;
2701 }
2702
2703 /**
2704 * Replaces a portion of the string builder with another string. The length of the inserted string does not have to
2705 * match the removed length.
2706 *
2707 * @param startIndex the start index, inclusive, must be valid
2708 * @param endIndex the end index, exclusive, must be valid except that if too large it is treated as end of string
2709 * @param replaceStr the string to replace with, null means delete range
2710 * @return this, to enable chaining
2711 * @throws IndexOutOfBoundsException if the index is invalid
2712 */
2713 public TextStringBuilder replace(final int startIndex, int endIndex, final String replaceStr) {
2714 endIndex = validateRange(startIndex, endIndex);
2715 final int insertLen = replaceStr == null ? 0 : replaceStr.length();
2716 replaceImpl(startIndex, endIndex, endIndex - startIndex, replaceStr, insertLen);
2717 return this;
2718 }
2719
2720 /**
2721 * Advanced search and replaces within the builder using a matcher.
2722 * <p>
2723 * Matchers can be used to perform advanced behavior. For example you could write a matcher to delete all
2724 * occurrences where the character 'a' is followed by a number.
2725 * </p>
2726 *
2727 * @param matcher the matcher to use to find the deletion, null causes no action
2728 * @param replaceStr the string to replace the match with, null is a delete
2729 * @param startIndex the start index, inclusive, must be valid
2730 * @param endIndex the end index, exclusive, must be valid except that if too large it is treated as end of string
2731 * @param replaceCount the number of times to replace, -1 for replace all
2732 * @return this, to enable chaining
2733 * @throws IndexOutOfBoundsException if start index is invalid
2734 */
2735 public TextStringBuilder replace(final StringMatcher matcher, final String replaceStr, final int startIndex,
2736 int endIndex, final int replaceCount) {
2737 endIndex = validateRange(startIndex, endIndex);
2738 return replaceImpl(matcher, replaceStr, startIndex, endIndex, replaceCount);
2739 }
2740
2741 /**
2742 * Replaces the search character with the replace character throughout the builder.
2743 *
2744 * @param search the search character
2745 * @param replace the replace character
2746 * @return this, to enable chaining
2747 */
2748 public TextStringBuilder replaceAll(final char search, final char replace) {
2749 if (search != replace) {
2750 for (int i = 0; i < size; i++) {
2751 if (buffer[i] == search) {
2752 buffer[i] = replace;
2753 }
2754 }
2755 }
2756 return this;
2757 }
2758
2759 /**
2760 * Replaces the search string with the replace string throughout the builder.
2761 *
2762 * @param searchStr the search string, null causes no action to occur
2763 * @param replaceStr the replace string, null is equivalent to an empty string
2764 * @return this, to enable chaining
2765 */
2766 public TextStringBuilder replaceAll(final String searchStr, final String replaceStr) {
2767 final int searchLen = searchStr == null ? 0 : searchStr.length();
2768 if (searchLen > 0) {
2769 final int replaceLen = replaceStr == null ? 0 : replaceStr.length();
2770 int index = indexOf(searchStr, 0);
2771 while (index >= 0) {
2772 replaceImpl(index, index + searchLen, searchLen, replaceStr, replaceLen);
2773 index = indexOf(searchStr, index + replaceLen);
2774 }
2775 }
2776 return this;
2777 }
2778
2779 /**
2780 * Replaces all matches within the builder with the replace string.
2781 * <p>
2782 * Matchers can be used to perform advanced replace behavior. For example you could write a matcher to replace all
2783 * occurrences where the character 'a' is followed by a number.
2784 * </p>
2785 *
2786 * @param matcher the matcher to use to find the deletion, null causes no action
2787 * @param replaceStr the replace string, null is equivalent to an empty string
2788 * @return this, to enable chaining
2789 */
2790 public TextStringBuilder replaceAll(final StringMatcher matcher, final String replaceStr) {
2791 return replace(matcher, replaceStr, 0, size, -1);
2792 }
2793
2794 /**
2795 * Replaces the first instance of the search character with the replace character in the builder.
2796 *
2797 * @param search the search character
2798 * @param replace the replace character
2799 * @return this, to enable chaining
2800 */
2801 public TextStringBuilder replaceFirst(final char search, final char replace) {
2802 if (search != replace) {
2803 for (int i = 0; i < size; i++) {
2804 if (buffer[i] == search) {
2805 buffer[i] = replace;
2806 break;
2807 }
2808 }
2809 }
2810 return this;
2811 }
2812
2813 /**
2814 * Replaces the first instance of the search string with the replace string.
2815 *
2816 * @param searchStr the search string, null causes no action to occur
2817 * @param replaceStr the replace string, null is equivalent to an empty string
2818 * @return this, to enable chaining
2819 */
2820 public TextStringBuilder replaceFirst(final String searchStr, final String replaceStr) {
2821 final int searchLen = searchStr == null ? 0 : searchStr.length();
2822 if (searchLen > 0) {
2823 final int index = indexOf(searchStr, 0);
2824 if (index >= 0) {
2825 final int replaceLen = replaceStr == null ? 0 : replaceStr.length();
2826 replaceImpl(index, index + searchLen, searchLen, replaceStr, replaceLen);
2827 }
2828 }
2829 return this;
2830 }
2831
2832 /**
2833 * Replaces the first match within the builder with the replace string.
2834 * <p>
2835 * Matchers can be used to perform advanced replace behavior. For example you could write a matcher to replace where
2836 * the character 'a' is followed by a number.
2837 * </p>
2838 *
2839 * @param matcher the matcher to use to find the deletion, null causes no action
2840 * @param replaceStr the replace string, null is equivalent to an empty string
2841 * @return this, to enable chaining
2842 */
2843 public TextStringBuilder replaceFirst(final StringMatcher matcher, final String replaceStr) {
2844 return replace(matcher, replaceStr, 0, size, 1);
2845 }
2846
2847 /**
2848 * Internal method to delete a range without validation.
2849 *
2850 * @param startIndex the start index, must be valid
2851 * @param endIndex the end index (exclusive), must be valid
2852 * @param removeLen the length to remove (endIndex - startIndex), must be valid
2853 * @param insertStr the string to replace with, null means delete range
2854 * @param insertLen the length of the insert string, must be valid
2855 * @throws IndexOutOfBoundsException if any index is invalid
2856 */
2857 private void replaceImpl(final int startIndex, final int endIndex, final int removeLen, final String insertStr,
2858 final int insertLen) {
2859 final int newSize = size - removeLen + insertLen;
2860 if (insertLen != removeLen) {
2861 ensureCapacityInternal(newSize);
2862 System.arraycopy(buffer, endIndex, buffer, startIndex + insertLen, size - endIndex);
2863 size = newSize;
2864 }
2865 if (insertLen > 0) {
2866 insertStr.getChars(0, insertLen, buffer, startIndex);
2867 }
2868 }
2869
2870 /**
2871 * Replaces within the builder using a matcher.
2872 * <p>
2873 * Matchers can be used to perform advanced behavior. For example you could write a matcher to delete all
2874 * occurrences where the character 'a' is followed by a number.
2875 * </p>
2876 *
2877 * @param matcher the matcher to use to find the deletion, null causes no action
2878 * @param replaceStr the string to replace the match with, null is a delete
2879 * @param from the start index, must be valid
2880 * @param to the end index (exclusive), must be valid
2881 * @param replaceCount the number of times to replace, -1 for replace all
2882 * @return this, to enable chaining
2883 * @throws IndexOutOfBoundsException if any index is invalid
2884 */
2885 private TextStringBuilder replaceImpl(final StringMatcher matcher, final String replaceStr, final int from, int to,
2886 int replaceCount) {
2887 if (matcher == null || size == 0) {
2888 return this;
2889 }
2890 final int replaceLen = replaceStr == null ? 0 : replaceStr.length();
2891 for (int i = from; i < to && replaceCount != 0; i++) {
2892 final char[] buf = buffer;
2893 final int removeLen = matcher.isMatch(buf, i, from, to);
2894 if (removeLen > 0) {
2895 replaceImpl(i, i + removeLen, removeLen, replaceStr, replaceLen);
2896 to = to - removeLen + replaceLen;
2897 i = i + replaceLen - 1;
2898 if (replaceCount > 0) {
2899 replaceCount--;
2900 }
2901 }
2902 }
2903 return this;
2904 }
2905
2906 /**
2907 * Resizes the buffer to at least the size specified.
2908 *
2909 * @param minCapacity the minimum required capacity
2910 * @throws OutOfMemoryError if the {@code minCapacity} is negative
2911 */
2912 private void resizeBuffer(final int minCapacity) {
2913 // Overflow-conscious code treats the min and new capacity as unsigned.
2914 final int oldCapacity = buffer.length;
2915 int newCapacity = oldCapacity * 2;
2916 if (Integer.compareUnsigned(newCapacity, minCapacity) < 0) {
2917 newCapacity = minCapacity;
2918 }
2919 if (Integer.compareUnsigned(newCapacity, MAX_BUFFER_SIZE) > 0) {
2920 newCapacity = createPositiveCapacity(minCapacity);
2921 }
2922 reallocate(newCapacity);
2923 }
2924
2925 /**
2926 * Reverses the string builder placing each character in the opposite index.
2927 *
2928 * @return this, to enable chaining
2929 */
2930 public TextStringBuilder reverse() {
2931 if (size == 0) {
2932 return this;
2933 }
2934
2935 final int half = size / 2;
2936 final char[] buf = buffer;
2937 for (int leftIdx = 0, rightIdx = size - 1; leftIdx < half; leftIdx++, rightIdx--) {
2938 final char swap = buf[leftIdx];
2939 buf[leftIdx] = buf[rightIdx];
2940 buf[rightIdx] = swap;
2941 }
2942 return this;
2943 }
2944
2945 /**
2946 * Extracts the rightmost characters from the string builder without throwing an exception.
2947 * <p>
2948 * This method extracts the right {@code length} characters from the builder. If this many characters are not
2949 * available, the whole builder is returned. Thus the returned string may be shorter than the length requested.
2950 * </p>
2951 *
2952 * @param length the number of characters to extract, negative returns empty string
2953 * @return The new string
2954 */
2955 public String rightString(final int length) {
2956 if (length <= 0) {
2957 return StringUtils.EMPTY;
2958 }
2959 if (length >= size) {
2960 return new String(buffer, 0, size);
2961 }
2962 return new String(buffer, size - length, length);
2963 }
2964
2965 /**
2966 * Clears and sets this builder to the given value.
2967 *
2968 * @see #charAt(int)
2969 * @see #deleteCharAt(int)
2970 * @param str the new value.
2971 * @return this, to enable chaining
2972 * @since 1.9
2973 */
2974 public TextStringBuilder set(final CharSequence str) {
2975 clear();
2976 append(str);
2977 return this;
2978 }
2979
2980 /**
2981 * Sets the character at the specified index.
2982 *
2983 * @see #charAt(int)
2984 * @see #deleteCharAt(int)
2985 * @param index the index to set
2986 * @param ch the new character
2987 * @return this, to enable chaining
2988 * @throws IndexOutOfBoundsException if the index is invalid
2989 */
2990 public TextStringBuilder setCharAt(final int index, final char ch) {
2991 validateIndex(index);
2992 buffer[index] = ch;
2993 return this;
2994 }
2995
2996 /**
2997 * Updates the length of the builder by either dropping the last characters or adding filler of Unicode zero.
2998 *
2999 * @param length the length to set to, must be zero or positive
3000 * @return this, to enable chaining
3001 * @throws IndexOutOfBoundsException if the length is negative
3002 */
3003 public TextStringBuilder setLength(final int length) {
3004 if (length < 0) {
3005 throw new StringIndexOutOfBoundsException(length);
3006 }
3007 if (length < size) {
3008 size = length;
3009 } else if (length > size) {
3010 ensureCapacityInternal(length);
3011 final int oldEnd = size;
3012 size = length;
3013 Arrays.fill(buffer, oldEnd, length, '\0');
3014 }
3015 return this;
3016 }
3017
3018 /**
3019 * Sets the text to be appended when {@link #appendNewLine() new line} is called.
3020 *
3021 * @param newLine the new line text, {@code null} means use the system default from {@link System#lineSeparator()}.
3022 * @return this instance.
3023 */
3024 public TextStringBuilder setNewLineText(final String newLine) {
3025 this.newLine = newLine;
3026 return this;
3027 }
3028
3029 /**
3030 * Sets the text to be appended when null is added.
3031 *
3032 * @param nullText the null text, null means no append
3033 * @return this, to enable chaining
3034 */
3035 public TextStringBuilder setNullText(String nullText) {
3036 if (nullText != null && nullText.isEmpty()) {
3037 nullText = null;
3038 }
3039 this.nullText = nullText;
3040 return this;
3041 }
3042
3043 /**
3044 * Gets the length of the string builder.
3045 * <p>
3046 * This method is the same as {@link #length()} and is provided to match the API of Collections.
3047 * </p>
3048 *
3049 * @return The length
3050 */
3051 public int size() {
3052 return size;
3053 }
3054
3055 /**
3056 * Checks whether this builder starts with the specified string.
3057 * <p>
3058 * Note that this method handles null input quietly, unlike String.
3059 * </p>
3060 *
3061 * @param str the string to search for, null returns false
3062 * @return true if the builder starts with the string
3063 */
3064 public boolean startsWith(final String str) {
3065 if (str == null) {
3066 return false;
3067 }
3068 final int len = str.length();
3069 if (len == 0) {
3070 return true;
3071 }
3072 if (len > size) {
3073 return false;
3074 }
3075 for (int i = 0; i < len; i++) {
3076 if (buffer[i] != str.charAt(i)) {
3077 return false;
3078 }
3079 }
3080 return true;
3081 }
3082
3083 /**
3084 * {@inheritDoc}
3085 */
3086 @Override
3087 public CharSequence subSequence(final int startIndex, final int endIndex) {
3088 if (startIndex < 0) {
3089 throw new StringIndexOutOfBoundsException(startIndex);
3090 }
3091 if (endIndex > size) {
3092 throw new StringIndexOutOfBoundsException(endIndex);
3093 }
3094 if (startIndex > endIndex) {
3095 throw new StringIndexOutOfBoundsException(endIndex - startIndex);
3096 }
3097 return substring(startIndex, endIndex);
3098 }
3099
3100 /**
3101 * Extracts a portion of this string builder as a string.
3102 *
3103 * @param start the start index, inclusive, must be valid
3104 * @return The new string
3105 * @throws IndexOutOfBoundsException if the index is invalid
3106 */
3107 public String substring(final int start) {
3108 return substring(start, size);
3109 }
3110
3111 /**
3112 * Extracts a portion of this string builder as a string.
3113 * <p>
3114 * Note: This method treats an endIndex greater than the length of the builder as equal to the length of the
3115 * builder, and continues without error, unlike StringBuffer or String.
3116 * </p>
3117 *
3118 * @param startIndex the start index, inclusive, must be valid
3119 * @param endIndex the end index, exclusive, must be valid except that if too large it is treated as end of string
3120 * @return The new string
3121 * @throws IndexOutOfBoundsException if the index is invalid
3122 */
3123 public String substring(final int startIndex, int endIndex) {
3124 endIndex = validateRange(startIndex, endIndex);
3125 return new String(buffer, startIndex, endIndex - startIndex);
3126 }
3127
3128 /**
3129 * Copies the builder's character array into a new character array.
3130 *
3131 * @return a new array that represents the contents of the builder
3132 */
3133 public char[] toCharArray() {
3134 return size == 0 ? ArrayUtils.EMPTY_CHAR_ARRAY : Arrays.copyOf(buffer, size);
3135 }
3136
3137 /**
3138 * Copies part of the builder's character array into a new character array.
3139 *
3140 * @param startIndex the start index, inclusive, must be valid
3141 * @param endIndex the end index, exclusive, must be valid except that if too large it is treated as end of string
3142 * @return a new array that holds part of the contents of the builder
3143 * @throws IndexOutOfBoundsException if startIndex is invalid, or if endIndex is invalid (but endIndex greater than
3144 * size is valid)
3145 */
3146 public char[] toCharArray(final int startIndex, int endIndex) {
3147 endIndex = validateRange(startIndex, endIndex);
3148 final int len = endIndex - startIndex;
3149 return len == 0 ? ArrayUtils.EMPTY_CHAR_ARRAY : Arrays.copyOfRange(buffer, startIndex, endIndex);
3150 }
3151
3152 /**
3153 * Gets a String version of the string builder, creating a new instance each time the method is called.
3154 * <p>
3155 * Note that unlike StringBuffer, the string version returned is independent of the string builder.
3156 * </p>
3157 *
3158 * @return The builder as a String
3159 */
3160 @Override
3161 public String toString() {
3162 return new String(buffer, 0, size);
3163 }
3164
3165 /**
3166 * Gets a StringBuffer version of the string builder, creating a new instance each time the method is called.
3167 *
3168 * @return The builder as a StringBuffer
3169 */
3170 public StringBuffer toStringBuffer() {
3171 return new StringBuffer(size).append(buffer, 0, size);
3172 }
3173
3174 /**
3175 * Gets a StringBuilder version of the string builder, creating a new instance each time the method is called.
3176 *
3177 * @return The builder as a StringBuilder
3178 */
3179 public StringBuilder toStringBuilder() {
3180 return new StringBuilder(size).append(buffer, 0, size);
3181 }
3182
3183 /**
3184 * Trims the builder by removing characters less than or equal to a space from the beginning and end.
3185 *
3186 * @return this, to enable chaining
3187 */
3188 public TextStringBuilder trim() {
3189 if (size == 0) {
3190 return this;
3191 }
3192 int len = size;
3193 final char[] buf = buffer;
3194 int pos = 0;
3195 while (pos < len && buf[pos] <= SPACE) {
3196 pos++;
3197 }
3198 while (pos < len && buf[len - 1] <= SPACE) {
3199 len--;
3200 }
3201 if (len < size) {
3202 delete(len, size);
3203 }
3204 if (pos > 0) {
3205 delete(0, pos);
3206 }
3207 return this;
3208 }
3209
3210 /**
3211 * Validates that an index is in the range {@code 0 <= index <= size}.
3212 *
3213 * @param index the index to test.
3214 * @throws IndexOutOfBoundsException Thrown when the index is not the range {@code 0 <= index <= size}.
3215 */
3216 protected void validateIndex(final int index) {
3217 if (index < 0 || index >= size) {
3218 throw new StringIndexOutOfBoundsException(index);
3219 }
3220 }
3221
3222 /**
3223 * Validates parameters defining a range of the builder.
3224 *
3225 * @param startIndex the start index, inclusive, must be valid
3226 * @param endIndex the end index, exclusive, must be valid except that if too large it is treated as end of string
3227 * @return A valid end index.
3228 * @throws StringIndexOutOfBoundsException if the index is invalid
3229 */
3230 protected int validateRange(final int startIndex, int endIndex) {
3231 if (startIndex < 0) {
3232 throw new StringIndexOutOfBoundsException(startIndex);
3233 }
3234 if (endIndex > size) {
3235 endIndex = size;
3236 }
3237 if (startIndex > endIndex) {
3238 throw new StringIndexOutOfBoundsException("end < start");
3239 }
3240 return endIndex;
3241 }
3242
3243 }